The Humpback whale around the British Isles

The Humpback whale (Megaptera novaeangliae)

                The humpback whale is a baleen whale that can reach 15m (51ft) in length. It is black or dark grey with long white pectoral flippers. It is found in the North Atlantic and is rarely seen on Atlantic coasts in Spring and Summer. It can be found in small groups and feeds on krill and shoaling fish (British Divers Marine Life Rescue, 2004-2012).

Humpback whales migrate nearly 10,000km in a year between their summer feeding grounds in near-polar waters and their winter breeding grounds in shallow, tropical waters. Observations of individuals suggest that oceanic populations are divided into a number of seasonal subpopulations which are not separated by geographical barriers (Baker et al. 1990). There are two populations of humpback whale, Southern hemisphere and Northern hemisphere. Their breeding cycles are unsynchronised and they do not interbreed (Johnson & Wolman, 1984). This was confirmed by Bakers et al. (1990) study of haplotypes which showed there was no overlap between the northern and southern populations, which was suggested to be due to strong maternal traditions regarding migratory destinations.

Humpbacks spend the summer on high latitude feeding grounds and migrate to low latitude winter breeding grounds, which is shown in figure 1. During the winter they are confined to shallow waters along coastlines and around oceanic islands which makes them vulnerable to modern whaling techniques. During the winter they fast and only eat during the summer (Johnson & Wolman, 1990).

In the eastern North Atlantic, during the summer humpbacks can be found from Iceland, Scotland and Norway to the Barents Sea, north of the Netherlands. In winter they can be found as far south as the Cape Verde Islands off the coast of Western Africa. In the western Atlantic they summer around the Denmark Strait off the east coast of Greenland, Labrador, Newfoundland and Nova Scotia and spend winter in the shallow waters around the Antillean chain of the West Indies. Each year humpbacks return to the same summer grounds (Johnson & Wolman, 1990).

Figure 1 – Geographical distribution of humpbacks whales (from Johnson & Wolman, 1984). Hatching = summer feeding grounds, stippling = winter grounds.

In the Northern hemisphere the diet of the humpback whale consists of krill, zooplankton, herring, Arctic cod and Pollock. Humpbacks distributions are heavily clumped in areas where food is abundant i.e. around the Newfoundland coast the humpbacks return coincides with the spawning of capelin and they feed at or below the surface (Johnson & Wolman, 1990).

The detection of humpbacks has been done in Britain using bottom-mounted hydrophones to detect whale song. Charif et al. (2001) did this from October 1996 to September 1998 and during this period, humpbacks were consistently detected between October and March from the Shetland-Faroe Islands to the southern waters west of the English Channel. This shows a south-westerly trend in their movements but there was no corresponding northern movement detected between April and September. This suggests that the offshore waters of the British Isles are used as a migratory corridor for humpback whales as they do between their feeding and breeding grounds (Charif et al. 2001).

References

Baker, C.S., Palumbi, S,R., Lambertsen, R.H., Weinrich, M.T., Calambokidis, J. & O’Brien, S.J. (1990). Influence of seasonal migration on geographic distribution of mitochondrial DNA haplotypes in humpback whales. Letters to Nature, 344:238-240.

British Divers Marine Life Rescue (2004-2012) Whales. Source: www.bdmlr.org.uk/index.php?page=whales-dolphins-amp-porpoises. Accessed: 28/02/2012.

Charif, R.A., Clapham, P.J. & Clark, C.W. (2001). Acoustic detections of singing humpback whales in deep waters off the British Isles. Marine Mammal Science, 17(4):751-768.

Johnson, J.H. & Wolman, A.A. (1984) The humpback whale Megaptera novaeangliae. Marine Fisheries Review, 45(40):30-37.

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REFERENCING

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For anyone that wants to reference anything they read in my journal, the citation is as follows:

Hill, R (date) Name of post. A Word From A Little One [blog] Date posted. Available at: http://missbeccyxoxo.blogspot.com/ [Accessed: date of last access]


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"There is very little we can do about invasive species in Britain and this is because of their biology and because of the practical difficulties."

The National Invasive Species Council defines an invasive species as “a non-native species whose introduction does or is likely to cause economic or environmental harm or harm to human, animal, or plant health”. There are many invasive species in the British Isles, from mammals to trees, amphibians to insects, and some of these species do have an impact on the native wildlife.

Possibly the most well known invasive species in Britain is the Grey squirrel (Sciurus carolinensis). It was introduced into this country from America at the start of the 20^th century and since then has spread widely and become a pest (Mountford, 2006). It is well known that the introduction of Grey squirrels has had an effect on native Red squirrels (Sciurus vulgaris). Grey squirrels are more efficient at exploiting food resources due to their size and hardiness and ability to neutralise toxins in acorns. This can explain how Grey squirrels have displaced Red squirrels in oak dominated woodland. Grey squirrels can also put on more body mass in the autumn months than Red squirrels, enhancing their ability to survive through the winter. Grey squirrels have also been known to pilfer the food caches of Red squirrels in the spring, impairing the Red squirrels breeding success (Gurnell, et al. 2004).

Grey squirrels also cause serious damage by stripping bark from young deciduous trees particularly beech (Fagus sylvatica), sycamore (Acer pseudoplatanus) and oak (Quercus spp.). They peel off the outer bark to get to the sap underneath. Trees are killed outright when they are ring-barked low to the stem, and less extensive stripping can aid fungal infection and stunt growth (Putman, 1989).

Methods of control include spring trapping, which kills the animal, live catch trapping, warfarin poisoning and shooting. Once the animal has been caught they need to be destroyed as it is an offence to release a grey squirrel back into the wild (Anon, 2011). It is best to attempt control between April and July and in highly dense areas. Traps have been shown to be more successful than immunocontraception (Orueta & Ramos, 2001). Resident squirrels in a population can be trapped or poisoned within 5 weeks, but can re-colonise isolated woodland in 3 months and non-isolated woodland within 1 month (Mayle, et al. 2007).

Controlling the Grey squirrel is very difficult because their biology allows them to manipulate habitats easily and eradication can be difficult and they can re-colonise and area quickly. There are also practical difficulties involved such as funding and man power.

Another invasive mammal in Britain is the North American Mink (Mustela vison), which was brought over to the UK in the 1920’s for fur farming, which was banned in 2003 (Bonesi & Palazon, 2007). As the trade declined animals escaped or were deliberately released and the first wild breeding was in 1956 (Smith et al. No date). Since their establishment in the UK, American Mink have had an effect on many species including water voles (Arvicola terestris), which have decreased in numbers by 97% since 1900 (Bonesi & Palazon,  2007). They also have an effect on water birds such as coots (Fulica atra) and moorhens (Gallinula chloropus) (Ferreras & MacDonald, 2001) and breeding seabirds. Between 1989-95, feral North American Mink caused widespread breeding failures in Common Gulls (Larsus canus), Black-headed Gulls (Chroicocephalus ridibundus) and Common Terns (Sterna hirundo) on small islands along the western coast of Scotland (Craik, 1997).

A few projects have shown that it is possible to eradicate and control the species given that there is enough resources and man power. Culling projects in the Western Isles have shown that using dogs to locate den sites may be very important in removing the last individuals in a low-desity population (Bonesi & Palazon, 2007). Eradication on isolated islands is more successful as isolation slows mink dispersal making re-colonisation more difficult (Nordström & Korpimäki, 2004). The current 5 year programme off the west coast of Scotland is costing £1.65 million, funded by EU LIFE, and is to protect ground-nesting birds. Thus far it has been successful with more than 220 mink caught (Moore, 2003).

On mainland Britain it seems that competition with otters is involved in the regulation of mink numbers (Harris, 2002). A research programme conducted by WildCRU supports this and suggests that otters are the dominant competitor and mink numbers have declined as a result of an increase in otters (“Management of American Mink and Interactions with Native Mustelids”).

In the case of the American Mink it seems that control is possible with enough resources, in terms of funding, knowledge and man power, through culling with dogs and traps in more isolated areas, as well as by increasing otter numbers to compete with mink on the mainland.

Other invasive mammals in Britain include the Muntjac deer (Muntiacus reevesi) from south-east Asia, the Chinese water deer (Hydropotes inermis) and the Edible dormouse (Glis glis) from Europe.

An example of an invasive bird species in Britain is the Ring-necked parakeet, also known as Rose-ringed parakeet, (Psittacula krameri) which originates from Africa and Asia. They were introduced in the UK in 1969 and there was an estimated 1500 wild birds by 1996 and numbers are increasing by approximately 25% a year. There were an estimated 6000 birds by 2002 (Butler, 2003). They compete for nest sites with other native hole-nesting birds such as nuthatches (Sitta europaea), and as a result nuthatch numbers have declined (Strubbe & Matthysen, 2009). They are considered an agricultural pest in their native range and have caused damage to crops in the UK (Marchant, 2011).

According to a research project carried out by DEFRA in 2008-09, habitat modification is the most effective and environmentally friendly way to control numbers. However it is unpopular with growers as it requires expert knowledge, effort and materials. Really the only effective way of trying to control numbers is by shooting. Natural England has relaxed the protected status of these birds to allow farmers to poison and shoot only problem birds on their own land (Anon, 2009).

In the case of the Ring-necked parakeet, their biology and the practical difficulties do hinder the control of the species. They breed well and due to their protection laws, culling them is not possible unless they are causing major crop damage on private land. Most forms of eradication for this species require knowledge, effort, and equipment and can be expensive.

Other invasive birds species in Britain include the Ruddy duck (Oxyura jamaicensis) from North America, the Canada Goose (Branta Canadensis) and the Eagle Owl (Bubo bubo) from Europe.

In regards to plants, one of the best known invasive species is the Rhododendron (Rhododendron ponticum). It was introduced to Britain in 1763 for ornamental purposes (Cross, 1975). Rhododendron easily invade woodland and can displace many native shrubs and trees and they are very tolerant of shade. In Killarney, Ireland, Rhododendron has formed a mutual relationship with another invasive species, the Japanese Sika deer (Cervus Nippon). The sika deer overgraze, making room for the Rhododendron to establish, and in return the rhododendron provides shelter (Simberloff & Van Holle, 1999).

Rhododendron is able to grow and establish on most acid soils displacing native flora and altering entire ecosystems. They create a lot of leaf litter and create dark environments that are near sterile. Control is normally herbicide application, post-cut application and cutting. Herbicide application can be done with a knapsack or stem injection but is proving costly with mixed success. Failure results in increased labour and material costs (Tyler, et al. 2006). The most common disposal method after removal is burning, but once the Rhododendron has been eradicated there may be extra costs in restoration of the habitat (Dehnen-Schmutz, et al. 2004).

The Rhododendron, therefore, is difficult to eradicate due to its biology, and the ability to colonise an area easily and quickly. It also requires a lot of man power and cost to remove and destroy it.

Another very invasive species of plant in Britain is Floating Pennywort (Hydrocotyle ranunculoides). It was accidentally introduced to the UK in the 1980’s by the aquatic nursery trade and it can now be found in many locations across southern England and south Wales. It forms dense mats in slow-flowing water bodies and outcompetes native aquatics. It causes deoxygenation of the water which also affects fish and invertebrates in that body of water. It can also clog drainage systems and sluices which can then cause localised flooding. It is hard to control due to its rapid growth but can be removed however, once removed it requires on-going monitoring (Kelly, 2006).

A recently discovered invasive species in Britain is the ‘Killer Shrimp’ Deikerogammarus villosus. It is an invasive species of predatory shrimp that was found in Grafham Water in Cambridgeshire in September 2010. It preys on native species of invterbrates such as damselflies and water boatmen as well as young fish. It can alter the ecology of a habitat and can cause extinctions of native species (Anon, 2010).

They can survive for up to 6 days out of water so can be spread by over land transport. They also have rapid growth, early sexual maturity and a large reproductive capacity with females laying up to 200 eggs per clutch. They are high risk in terms of dispersal, establishment and ecological damage. They can change an environment by displacing species within an ecosystem which leads to changes in organic matter cycling such as eliminating amphipod and non-amphipod leaf shredders which will affect leaf-litter processing (MacNiel, et al. 2010).

The Environment Agency has begun the Check Clean Dry campaign. When you leave a body of water, check your clothing and equipment for organisms. If you find any, put them back into the body of water where they were found. Clean all equipment, footwear and clothing thoroughly. Dry all equipment and clothing properly and ensure you do not transfer water elsewhere (The Environment Agency, 2011). This campaign is to try and stop the spread of this predatory shrimp in the hope that it will not cause any long term damaging effects.

Other invasive plant species include Oxford ragwort (Senecio squalidus) from Sicily, Japanese knotweed (Fallopia japonica) and the Water fern (Salvinia minima) from Tropical America.

Not all invasive species in Britain cause damage or have harmful effects. These include the European pond terrapin (Emys orbicularis), marsh frog (Pelophylax ridibundus) from Eastern Europe and European tree frog (Hyla arborea). Non harmful trees and plants include the North American Red Oak (Quercus rubra), Cricket Bat Willow (Salix alba caerulea) from south-east Asia, Lombardy poplar (Populus nigra) from Italy, garden auricular (Primula auricular) from Europe, Heart-leaved dewplant (Aptenia cordifolia) from South Africa and the Siberian Iris (Iris siberica).

                Taking into account all of the example of invasive species I have mentioned, I partly agree with the statement “there is very little we can do about invasive species in Britain and this is because of their biology and because of the practical difficulties”. I partly agree because there are some things we can do about certain invasive species in the UK such as mink. They can be controlled by culling, trapping and hunting as well as more natural ways such as being out-competed by the native species of otter, so as otter numbers increase the mink numbers decrease, it will just take time. The Floating pennywort can also be controlled with constant management even though it can be costly in terms of time and resources.

Some species can be partially controlled such as the ‘killer shrimp’. Their movements can partially be controlled through care taken by people that have been involved with bodies of water where the species is present, but the species may never be able to be eradicated completely. I believe the same can be said for the Ring-necked parakeet. With habitat modification and extra effort put in by land owners to catch and shoot the parakeets their numbers could be kept under control.

I believe some species are not able to be controlled, such as the Grey squirrel because their numbers have increased so enormously and their biology enables them to exploit many niches and food resources, and their ability to outcompete and displace native species such as the Red squirrels.

References

Anon. (2009) Statement on Monk & Ring-necked Parakeets. Accessed: 16/11/11. Source: http://www.naturalengland.org.uk/about_us/news/2009/031009.aspx

Anon. (2010) ‘Alien ‘killer shrimp’ Found in UK’. BBC News online. 9^th September. Accessed: 17/11/11. Source: http://www.bbc.co.uk/news/science-environment-11246642

Anon. (2011). BASC Grey Squirrel Control. Accessed: 16/11/11. Source: http://www.naturalengland.org.uk/about_us/news/2009/031009.aspx

Bonesi, L. & Palazon, S. (2007) The American Mink in Europe: status, impacts & control. Biological conservation 134(4):470-483.

Butler, C.J. (2003) Population Biology of the Introduced Rose-Ringed Parakeet Psittacula krameri in the UK. Doctoral thesis, University of Oxford.

Craik, C. (1997) Long-term effects of North American Mink (Mustela vison) on seabirds in Western Scotland. Bird Study 44(3):303-309.

Dehnen-Schmutz, K., Perrings, C. & Williamson, M. (2004) Controlling Rhododendron ponticum in the British Isles: an economic analysis. Journal of Environmental Management 70(4):323-332.

Ferreras, P. & Macdonald, D.W. (2001) The impact of American Mink Mustela vison on water birds in the upper Thames. Journal of Applied Ecology 36(5):701-708.

Gurnell, J., Wauters, L.A., Lurz, P.W.W. & Tosi, G. (2004) Alien species and interspecific competition: effects of introduced eastern grey squirrels on red squirrel population dynamics. Journal of Animal Ecology 73(1):26-35.

Harris, S. (2002) Hunting With dogs: Hearing On The Evidence (9-11 September 2002). Session 1C: Managing and Controlling the Quarry Species (fox, deer, hare and mink) populations.

Kelly, A. (2006) Removal of invasive floating pennywort Hydrocotyle ranunculoides from Gillingham Marshes, Suffolk, England. Conservation Evidence 3:52-53.

MacNiel, C., Platvoet, D., Dick, J.T.A., Fielding, N., Constable, A., Hall, N., Aldridge, D., Renals, T. and Diamond, M. (2010) The Ponto-Caspian ‘killer shrimp’, Dikerogammarus villosus (Sowinsky, 1894), invades the British Isles. Aquatic Invasions 5(4):441-445.

Marchant, J., (2011) Ring-necked Parakeet, Psittacula krameri. Accessed: 16/11/11. Source: https://secure.fera.defra.gov.uk/nonnativespecies/factsheet/factsheet.cfm?speciesId=2886

Mayle, B., Ferryman, M. & Pepper, H. (2007) Controlling Grey Squirrel Damage to Woodlands. Forestry Commission Publication. Accessed: 16/11/11.  Source: http://www.forestry.gov.uk/pdf/fcpn004.pdf/$FILE/fcpn004.pdf

Moore, N.P., Roy, S.S. & Helyar, A. (2003) Mink (Mustela vison) eradication to protect ground-nesting birds in the Western Isles, Scotland, United Kingdom. New Zealand Journal of Ecology 30(4):443-452.

Mountford, E.P. (2006) Long-term patterns and impacts of grey squirrel debarking in Lady Park Wood young-growth stands (UK). Forest Ecology and Management 232(1-3):100-113.

Nordström, M. & Korpimäki, E. (2004) Effects of island isolation and feral mink removal on bird communities on small islands in the Baltic Sea. Journal of Animal Ecology 73(3):424-433.

Orueta, J.F. & Ramos, Y.A. (2001) Methods to Control and Eradicate Non-native Terrestrial Vertebrate Species. Council of Europe Publishing.

Putman, R.J. (1989) Mammals as Pests. Chapman and Hall Ltd.

Simberloff, D. & Van Holle, B. (1999) Positive interactions of nonindigenous species: invasional meltdown? Biological Invasion 1(1):21-32.

Smith, S., Booy, O., Wade, M. & White, V. (no date) Non-Native Species Secretariat publication. (Source: https://secure.fera.defra.gov.uk/nonnativespecies/index.cfm?sectionid=47

Strubbe, D. & Matthysen, E. (2009) Experimental evidence for nest-site competition between invasive ring-necked parakeets (Psittacula krameri) and native nuthatches (Sitta europaea). Biological Conservation 142(8):1588-1594.

The Environment Agency. (2011) Non-native invasive shrimp found in UK waters. Accessed: 17/11/11. Source: http://www.environment-agency.gov.uk/homeandleisure/wildlife/123281.aspx

Tyler, C., Pullin, A.S. & Stewart, G.B. (2006) Effectiveness of Management Interventions to Control Invasion by Rhododendron ponticum. Environmental Management 37(4):513-522.

MANAGEMENT REVIEW - CARNIVORES IN ZOOS

Legislation regarding zoo management

                In 1999, the EC Zoos Directive was a major step forward in European legislation concerning zoos and resulted in the closure of some very poor zoos. It set out requirements for licensing and inspection, proper record keeping, standards of animal care and requirements for education and conservation. It states that zoos not directly involved in captive breeding or reintroduction programmes should be involved at least with supporting research and training. The UK’s Zoo Licensing Act 1981 is also very involved with the management of zoos.

                The Secretary of State’s Standards of Modern Zoo Practice (SSSMZP) is a guideline of expected standards for zoos and has five main principles which are based on the five freedoms:

1.       Provision of food and water à regards health and hygiene aspects as well as appropriateness of the quality, quantity and variety of food provided, taking into account species, sex, age, reproductive condition etc.

2.       Provision of a suitable environment à includes physical features of the environment and appropriateness for the species and minimizing the possibility of escape. Also includes health and safety considerations (electrical equipment, broken barriers etc) and hygiene (cage cleaning and waste disposal etc).

3.       Provision of health care à Provision of veterinary care and disease prevention.

4.       Provision of opportunity to express most normal behaviours à physical and social environments that promote behaviour similar to that seen in wild animals.

5.       Provision of protection from fear and distress à appropriate environments and the ability from avoid human contact.

There are a number of other organisations that help the law govern zoos and provide guidelines and advice. There include the British and Irish Association of Zoos and Aquariums (BIAZA), the European Association of Zoos and Aquiariums (EAZA), the Association of Zoos and Aquariums (AZA) in North America, the Australasian Regional Association of Zoos and Aquariums (ARAZA), the Association of British Wild Animal Keepers (ABWAK) and DEFRA (Hosey et al. 2009).

Behaviour

Animals, including carnivores, have been kept in captivity since pre-historic times, and there are many principles to consider when housing carnivores so that the management is beneficial and influences natural behaviours and removes factors that have adverse effects. These principles include taking into account the animal’s natural territory and habitat, sleeping patterns, diet and foraging patterns and social structure (Blackshaw, 1986). Poor management and housing can lead to the animals showing abnormal behaviours, known as stereotypic behaviours, which are repetitive and apparently functionless. These include activities such as pacing, excessive licking and sometimes self-mutilation. High levels of stereotypy can indicate poor welfare (Kleiman et al., 2010).

The extent to which animals can show species-typical behaviours depends on the opportunities provided by their environment, i.e. prey catching behaviour may not be possible in most zoo environments. Behavioural diversity is a good measure of how closely the zoo environment allows the animals to perform species-specific behaviours. The significance of learning is that it permits the animal to detect patterns and relationships between objects and events in their environment. If an animal is prevented from performing a natural behaviour it is motivated to do, it can lead to frustration, and over long periods can lead to adverse effects on welfare (Hosey et al 2009).

Preventing natural behaviours in captive animals can lead to stress and frustration and impair the development of certain regions of the brain involved in behavioural sequencing. This limits the animal’s ability to behave appropriately and natural, therefore inducing stereotypical behaviours. Stereotypy is more commonly observed in naturally wider-ranging species such as polar bears (a typical polar bear enclosure is one-millionth the size of its minimum natural home range) (Clubb & Mason, 2003).

Stereotypic behaviours represent a divergence from the behaviour of wild animals and can indicate Central Nervous System problems, which affects the animal’s suitability for re-introduction (Mason et al., 2007).

                Stereotypic behaviours can be present due to a number of factors. In the fennec fox (Vulpes zerola) abnormal behaviours increase with visitor numbers, in leopard cats (Felis bengalensis) when housed near predators and/or without hiding places and in leopards (Panthera pardus) when kept in holding pens and in many other carnivorous species, abnormal behaviours increase on ‘starve days’ (days when the animals are not fed). There are a number of methods used to try and reduce and prevent the occurrence of stereotypical behaviours (from Mason et al., 2007):

1.        Genetic selection – abnormal behaviours are selected against. It is national policy in the Netherlands to select against abnormal behaviours on mink ranches. Zoos occasionally do similar but indirectly, by not breed from animals showing high levels of stereotypical behaviour. It is not often used in zoos and is inappropriate for animals that have the potential for release. It also does not tackle the underlying cause of the behaviour.

2.       Pharmacological compounds – serotonin-reuptake inhibitors (‘Prozac’) is widely used in companion animals and has been used in captive bears and primates and has previously successfully reduced stereotypic behaviours in a polar bear who had been pacing and fur plucking for 20 years, but it is not always successful and again, does not tackle the underlying cause of the behaviours.

3.       Positive reinforcement of other behaviour – alternative behaviours reinforced with reward has been successful in some zoo cases. It was used to improve captive dolphin welfare and stop the animal from repetitively regurgitating after a meal. The dolphin was rewarded for not regurgitating its food. This method proved successful but is very labour intensive and does not deal with the original cause of the behaviour.

4.       Physical prevention or punishment – using objects to obstruct the usual pacing pathways of an animal, or using unpleasant tastes to discourage repetitive licking of objects in the enclosure. Can be successful but does not tackle the underlying problems.

5.       Environmental enrichment – using novelty objects to change the everyday environment of the animal, and change their daily routine. This gives the animals the opportunity to perform natural behaviours and they can choose whether to interact with the object. Enrichment can also include altering the physical environment within the enclosure or altering the normal feeding regime. This tackles the root problem causing stereotypical behaviour is most commonly used.

It has been shown through previous studies that stereotypical behaviours are predicted by

natural ranging behaviour (home range size and travel distance) more so than foraging behaviour (e.g. hunting). Wider-ranging natural lifestyles also predict high infant mortality. Enclosures and enrichment focussing more on ranging behaviours (e.g. more dens, more space, more variability) may prove more effective in preventing and reducing stereotypical behaviour and improving welfare (Clubb & Mason, 2007).

Feeding

                There are a few ways of feeding captive carnivores and different types of food they can be fed, such as whole carcasses, feeding prepared meat and soft-textured feeding. Feeding a whole carcass often requires additional supplementation as the animal will often selectively eat certain parts of the carcass, resulting in an inadequate diet. There is also an issue with the zoo being able to maintain a sustainable supply of whole carcasses. In many societies, the feeding of whole carcasses is disliked by the viewing public (Young, 1997).

                Prepared meat if often used as is usually skinned muscle from livestock, and is also nutritionally inadequate so requires supplementation. A problem with this feed type is reduced sensory input. In the wild, a carnivore uses its senses for food identification. They lean over the prey and use their whickers to feel the direction of the fur or feathers as they often have a set method for dissecting their prey. Whiskers also have mechano-receptors which links to the canines suggesting that the teeth can ‘feel’ their way to the killing bite. Young carnivores learn what is appropriate by observing what the mother brings back after a hunt. For successful re-introduction of captive animals they need experience in identifying appropriate prey species and utilizing the carcass (Young, 1997).

                Management programmes have shown that appetites and body condition improve if the animals are fasted for 1 or 2 days a week (known as starve days). Either no food is fed or a large bone is provided. This simulates the feeding of most carnivores in the wild as they will not successfully hunt every day. Feeding bones has an additional function in promoting dental health and natural behaviour and therefore provides enrichment (Tilson et al. 1994).

                Diet quantities should be increased by 10-20% in animals housed outdoors during the winter and decreased in the summer and increased to ad lib during lactation. Commercially prepared diets (also known as soft-textured) are commonly fed, however recent studies show an excess of vitamin A and phytoestrogens, and some deficiencies in taurine but manufacturers are now correcting the health problems. No other supplements should be necessary with a properly formulated diet (Tilson et al 1994).

                Regulation 26.3(a) of the Animal By-Products Regulations 2005 states that zoos require authorisation from their local Animal Health Office before they can feed animal by-products to other animals on their premises (Hosey et al 2009).

                Timing of feeding can influence behaviour if its predictability allows the animals to anticipate it, which can lead to an increase in aggression or stereotypic pacing. Captive feeding routine may also differ from the natural activity of the wild animals. For example, a lot of carnivores, such as lions, generally hunt at night as they have good night vision and their prey is at a disadvantage.

                Behaviour can also be strongly influenced by the way food is presented. Multiple feedings of hidden food for leopard cats (Felis bengalensis) results in a decrease in pacing but an increase in locomotory/exploratory behaviour (Hosey et al. 2009).

Environment and Housing

                An important variable in the environment is space. Generally, zoo enclosures are smaller than the animal’s natural home range, especially carnivores which generally have a large home range to find food. Restricted space is a causal factor in the promotion of stereotypy development. Different animals are affected differently by their captive environment, for example, wolves (Canis lupus) spend more time at rest in larger enclosures but behavioural diversity appears to be more related to group composition than enclosure size.

                Different species use different parts of their enclosure in different ways and some areas more frequently than others. Cats mostly show stereotypical pacing at enclosure edges which is an artificial territory boundary and they can see visitors and keepers approaching. Chimpanzees prefer more elevated parts of the enclosure whereas gorillas prefer to stay on the ground (Hosey et al 2009).

                General consensus is that space is less important than the quality of the space within the environment in regards to structural complexity. Many zoos have moved towards having more naturalistic enclosures which simulate the natural habitat of the animal. With this comes an increase in complexity and size and is accompanied by more naturalistic behaviours (Hosey et al. 2009).

                At the very least housing should ensure that the five freedoms are fulfilled. Very little is known about the exact requirements of many species so past experience and knowledge is used to meet the animals basic needs. 

                It is also important to keep animals within the right social structure. With the exception of lions, all felids are generally solitary but in zoos are often kept in pairs or trios. Studies have shown that smaller cats housed in groups of greater than two were less likely to reproduce than those kept in pairs and spend more time pacing. It has been suggested that felids of this type should be housed singly and introductions of males and females made for breeding purposes or enrichment. It has been reported that there is a positive relationship between enclosure size and successful reproduction (Mellen & Wildt, 1998).

Enrichment

                Enrichment is any change to an animal’s environment or routine that is implemented to improve health and physical and mental well-being and aims to generate a behavioural change in the animal and prevent or reduce stereotypies (Hosey et al. 2009).

There are different types of enrichment:

Food-based enrichment: centred on food i.e. new presentation or types of food.

Physical enrichment: change to the structural environment or the provision of objects for manipulation.

Sensory enrichment: anything that stimulates the animals senses i.e. blood trails.

Social enrichment: interactions with other animals or people.

Cognitive enrichment: additions to the environment that require problem solving etc for mental stimulation (Hosey et al. 2009).

Many experiments have been done on the effects of enrichment on carnivore behaviour. One experiment was conducted on cheetahs that were regularly seen to be pacing. Temporal feeding (time of feed) and spatial feeding (location of food) were altered and olfactory enrichment was provided in the form of fresh ungulate dung. This increased variation did prove to reducing the pacing behaviour of the cheetahs (Quirke & O’Riordan, 2011).

                A study on captive coyotes showed that making the feeing regime unpredictable increased the frequency of natural behaviours such as marking and howling. Varying the feeding time between predictable and unpredictable can be beneficial in promoting varying behaviours (Gilbert-Norton et al. 2009).

                Foraging behaviour is an essential part of an animal’s survival so enrichment to stimulate foraging could be crucial. Previous work on this includes artificial moving prey to encourage natural hunting in servals (Felis serval) and cheetahs (Acinonyx jubatus). In European wild cats (Felis s. Sylvestris) electronic feeders promoted natural hunting and prevented behavioural problems. In tigers (Panthera leo) stereotypic behaviour was decreased by manipulable feeders. Hiding food around the enclosure reduced stereotypies in black bears (Ursus americanus) and increased searching behaviour in bush dogs (Speothos venaticus) (Kistler et al. 2009).

                An experiment was done on red foxes (Vulpes vulpes) which involved 3 methods of enrichment using electronic feeders combined with: a self-service food box, allowing control over food; manually scattering food unpredictably; and an electronic dispenser delivering food unpredictably. The aim was to stimulate searching behaviour. The diversity of behaviour and overall activity was increased, especially when the foxes had control over their food. Manual scattering and the electronic dispenser enhanced food searching behaviour indicating that foraging behaviour can be stimulated when food is delivered unpredictably (Kistler et al. 2009).

                Hiding spaces are important for clouded leopards (Neofelis nebulosa) and providing them with areas such as caves or dense areas of foliage so they can hide from view from the public can reduce stereotypical behaviours and make the animals more comfortable. Forms of sensory enrichment can include leaving piles of ungulate dung and blood in exhibits and playing the sounds of other animals into the exhibits. Social enrichment in carnivores can be difficult as they are often territorial and can be aggressive towards intruders in their territory (Hosey et al 2009).

                In regards to social enrichment, it has been suggested to rotate members of a pair on exhibit daily i.e. have the male on exhibit in the morning and the female in the afternoon. This way the animals can explore the exhibits and any scent marks the other individual left behind. This has been shown to increase the activity of Siberian tigers (Mellen & Wildt, 1998).

Breeding and conservation

                Reproduction and mating strategies are very different between species and there are many factors that can influence reproductive success. A behaviourally competent animal could be expected to show courtship behaviours in the right situation, such as when paired with a member of the opposite sex of the same species, as well as show the appropriate behaviours after birth such as good parenting behaviours, but animals in captivity sometimes don’t show these behaviours. It is also important to monitor the reproductive status of animals to know when to bring animals together for mating and when to make changes to the animal’s environment. Sometimes it is necessary for zoos to interfere with the rearing process, such as when a mother abandons her young (Hosey et al. 2009).

                Captive breeding and re-introduction projects are fundamental in the conservation of species, however only one-in-three captive-born carnivores survive in the wild. The animals in captivity do not have the natural behaviours needed for survival in the wild as they have a lack of hunting skills and little fear of humans. They are usually killed due to hunting, collisions with vehicles, starvation, disease or lack of social interactions such as pack formation and group hunting (University of Exeter, 2008). There is a lot of focus on carnivores as a flagship species for conservation societies, as they have visual appeal.

                Carnivores are long-lived, have extensive social learning and relatively long generations which can mean populations struggle to recover after significant decline. A number of reviews on carnivore conservation have proposed that in-situ conservation (habitat protection/restoration, prey densities) may be more effective than releases back into the wild (Jule et al. 2008).

It has been shown statistically that release projects are more likely to succeed when wild-caught animals are used. The most common cause of death for wild caught and captive-bred animals is by human means (hunting, poisoning, collisions with cars etc.) Often the initial conflict with humans is not resolved by the time the animals are released. Also, starvation, inter-species aggression (such as lions killing smaller carnivore’s e.g. wild dogs) and disease (e.g. rabies and distemper) were most common in captive-bred animals. This shows that captivity negatively influences the chances of survival of the animals because they lack the necessary skills to hunt and socialise, they are more adapted to human contact and lack the immunity of wild individuals. Wide-ranging carnivore’s poor response to captivity results in reduced breeding success and high stereotypy which can also affect reintroduction success (Jule et al. 2008).

It is also important to consider the aspects of social behaviour prior to release. A founder group composition is likely to determine success whereas persistence will depend on the formation of new groups to maintain reproductive capacity. Keeping animals in their original groups can also reduce stress.  Using a pre-release enclosure has been shown to increase re-introduction success (known as ‘soft-release’). Animals familiarise themselves with the release area (Hayward & Somers, 2009).

Conclusion

In conclusion, given all the information that I have presented, I believe that modern zoos are doing very well in better understanding the needs of carnivores in captivity and are changing their management accordingly. Obviously if enclosures could be much bigger in accordance with natural territory size, that would be a benefit, however there are obvious restraints for this. I think zoos have done well in finding alternatives for this and stereotypical behaviours, such as environmental and feeding enrichment and are working well to maintain this. I also believe zoos are integral in conservation of species with reintroduction programmes involving wild-caught animals in the correct social situation as well as ones bred in captivity are vital and the correct measures are being taken to do this.

References

Blackshaw, J.K. (1986) Notes on some topics in Applied Animal Behaviour 3^rd Edition. Chapter 10: Wild Animals In Captivity.

Clubb, R. & Mason, G. (2003) Captivity effects on wide-ranging carnivores. Nature 425:473.

Clubb, R. & Mason, G. (2007) Natural behavioural biology as a risk factor in carnivore welfare: How analysing species differences could keep zoos improve enclosures. Applied Animal Behaviour

Gilbert-Norton, L.B., Leaver, L.A. & Shivik, J.A. (2009) The effect of randomly altering the time and location of feeding on the behaviour of captive coyotes (Canis latrans). Applied Animal Behaviour Science 120(3-4):179-185.

Hayward, M.W. & Somers, M.J. (2009) Re-introduction of Top-Order Predators. Chapter 12 – The role of social behaviour in carnivore re-introductions. Blackwell Publishing.

Hosey, G., Melfi, V. & Pankhurst, S (2009) Zoo Animals: Behaviour, Management and Welfare. Oxford University Press.

Jule, K.R., Leaver, L.A. & Lea, S.E.G. (2008) The effects of captive experience on reintroduction survival in carnivores: A review and analysis. Biological Conservation 141:355-363.

Kistler, C., Hegglin, D., Würbel, H. & König, B. (2009) Feeding enrichment in an opportunistic carnivore: The red fox. Applied Animal Behaviour Science 116(2-4):260-265.

Kleiman, D.G., Thompson, K.V. & Baer, C.K. (2010) Wild Mammals in Captivity: Principles and Techniques for Zoo Management, 2^nd Edition, Pg. 14. University of Chicago Press.

Mason, G., Clubb, R., Latha,, N. & Vickery, S. (2007) Why and how should we use environmental enrichment to tackle stereotypic behaviour? Applied Animal Behaviour Science 102(3-4):163-188.

Mellen, J.D. & Wildt, D.E. (1998) Husbandry Manual for Small Felids. American Zoo and Aquarium Association.

Quirke, T. & O’Riordan, R.M. (2011) The effect of different types on enrichment on the behaviour of cheetahs (Acinonys julbatus) in captivity. Applied Animal Behaviour Science 133(1-2):87-94.

Tilson, R., Brady, G., Traylor-Holzer, K. & Armstrong, D. (1994) Management and Conservation of Captive Tigers, 2^nd Edition. Chapter 4: Nutrition, Food Preparation and Feeding.

University of Exeter (2008) Captive Carnivores Not up To Wild Living. Science Daily (online) 21^st January. Source: www.sciencedaily.com/releases/2008/01/080121080406.htm. Last accessed: 20/Dec/11.

Young, R.J. (1997) The importance of food presentation for animal welfare and conservation. Proceedings of the Nutrition Society 56:1095-1104

“Explaining to the general public and to conservation volunteers why conservation often involves altering the environment.”

The UK has many diverse and varying habitats, but over time these habitats and the species within them come under threat.  If a habitat is left undisturbed for a long period of time, it undergoes a process called succession. This is when a habitat naturally changes from one ecosystem to another. For example, on heathland, over time trees and scrub can begin to grow from seeds naturally being blown over the area. As the trees and scrub spreads, they shade natural flora and can eventually change the composition of the soil so the native flora can never grow back. Succession, therefore, needs to be managed to keep the variety and diversity of habitats and species.  

                Succession can be managed in a number of ways, such as coppicing and complete woodland clearance, to cattle or livestock grazing. All of these things involve altering the environment, but in a good way, a way that prevents important habitats from being lost to succession. An example of this can be seen at Lincoln’s Couth Common. Scrub has started to grow around the common and is shading the natural grassland. This scrub is being cut back to keep the grassland in its natural state.

                Invasive species also need to be managed, for example, Rhododendron plants. Rhododendron is very invasive and spreads very quickly. It then shades natural flora and the fallen leaves acidify the soil, therefore prevent plant regeneration as the soil composition has changed. Invasive plants like this need to be cut away and destroyed before they have a chance to permanently change the soil composition. This is being done at Swanholme Lakes in Lincoln, where Rhododendron and Birch trees are being cut down and burnt to allow the natural heathland to regenerate.

                Coppicing is a traditional woodland management practice which involves cutting sections of woodland on a regular cycle. The timber produced can be used for fencing and fuel. Once the trees have been coppiced there is a clearing. This allows warmth and light to reach the ground, allowing plant and insect life to flourish and biodiversity increases. Over the years the trees re-grow with many stems and will eventually block out the light again, therefore the coppicing needs to be carried out regularly. Coppicing is being done on Marley Common, in West Sussex. It is an area of lowland heath that is being invaded by chestnut trees, as well as others such as birch. Areas of Chestnut are being coppiced to allow sunlight and warmth to the ground, so the natural flora has a chance to regenerate.

                Cattle grazing is also an effective way of managing succession, especially in heathland. Grazing increases plant species richness and reduces leaf litter depth and the cover of dwarf shrubs and scrub species (Bullock et al 1997). Seeds will also get spread in their droppings, spreading the diversity of plant life. They also spread nutrients from one place to another. Grazing does not prevent tree encroachment however, but free-range grazing combined with tree cutting are suitable for management of species-rich heathland with grass-heather mosaics (Bokdam et al. 2000). Grazing reduces the dominance of strongly competitive grasses and allows the more delicate heathers and flowers to flourish, leading to a more open landscape and a variety of micro-climates.

The Cotswold Grazing Animals Project aims to restore, conserve and enhance flower-rich limestone grassland in the Cotswolds. This area is made up of many kinds of lime-loving flora, as well as a variety of insects and birds, and over half of the remaining grassland is protected by SSSI’s or National Nature Reserves. The decline in habitat is due to the intensification of farming by conversion to arable land and ploughing and re-seeding with vigorous grasses. A lack of grazing allows coarse grasses to dominate; swamping low-growing grasses and herbs and eventually the habitats is lost under trees and scrub.  The cattle have been introduced to get back the old, rare limestone grassland.

                Other ways of positively altering the environment is creating habitats, such as ponds. Pond creation encourages threatened species, such as newts, and creates wetland habitats for many other species. A range of depths also encourages waterside plant life, which provides cover for wetland species as well as many others such as birds. The South Yorkshire Ponds Project aims to restore dried out or silted up ponds to benefit wildlife and they are also conducting pond surveys. A Lowland Pond Survey was carried out in England, Wales and Scotland by Pond Conservation in 1998. The aims were to estimate the number of ponds in lowland Britain and to provide and estimate of pond ecological quality in terms of biodiversity. They found that ponds are very important for biodiversity. Almost half of British wetland plant species, including uncommon species, were found in the ponds. Nearby intensive land use has an impact on the biodiversity of the pond. New ponds have a high conservation value and are home to a wide variety of wetland plant species and are less likely to be effected by nutrient enrichment.

                Sometimes a habitat is altered so convert it back to its pre-agricultural state. This is called re-wilding. It includes such things as grazing and creating wetland habitats by blocking drainage routes, as well as planting woodlands and hedgerows. Planting trees and allowing some succession around previously agricultural areas encourages the local plant life to grow back and local species to return.

                Re-wilding is also a part of the National Trusts “Living Landscape” project. This is a project to re-connect and revitalise remaining species rich habitats all over the country. Agricultural areas are undergoing re-wilding to encourage species back, and then they are being reconnected to other spaces in rural and urban areas by natural corridors, to allow the movement of species to other areas of the country. An example of this is the Great Fen Project. This project aims to restore wetland between Huntington and Peterborough and reconnecting habitats. The area is first restored by cutting back scrub and trees to connect the open habitats of Woodwalton and Holme Fens, which will enhance the value of the site. The two habitats will then be joined to remove the arable barrier for less mobile invertebrates and plants. This will also provide more space for habitats and species and will allow a network of paths and waterways to be developed, and will create one of the largest nature reserves in England. The reserve will then be expanded further and visitor centres and other infrastructure will be developed.

                Another form of habitat management which alters the environment is controlled burning. Controlled burning is an ancient practice commonly seen in heath land.  It promotes the regeneration of seeds. It also prevents the spread of trees and scrub that encroach due to succession. It is also undertaken in woodland and forests and can be done periodically to avoid bird nesting times. Period fire favours understory species that require more open habitats. A mosaic of burned and unburned areas maximise the “edge effect”, which promotes a large and varied wildlife population. It also stimulates fruit and seed production and increases the amount of browse material for species such as deer (Wade, D et al 1989).

                The New Forest National Park use controlled burning on their heathland to maintain gorse and scrub. These plants would quickly shade out and replace highly valued heathland plants and animals if controlled burning was not used to manage it. Rare species such as the Dartford Warbler rely on the rotational burning of gorse to produce the dense growth the like. Controlled burning in the New Forest revitalises plants on the heath by removing old growth and allowing nutritious young plants to re grow for grazing. It also provides thick cover for nesting and shelter.

                Habitats can be managed and maintained in a variety of ways as I have shown. These management techniques all involve altering the environment, but they do so in a way that promotes biodiversity and healthy habitats.

References

Bokdam J, Gleichman J.M (2000) Journal of Applied Ecology 37(3):415-431. Effects to grazing by free-ranging cattle on vegetation dynamics in a continental north-west European heathland.

Bullock J, Pakeman R (1997) Biological Conservation 79(1):1-13. Grazing of lowland heath in England: Management methods and their effects on heathland vegetation.

Wade D, Lunsford J (1989) A Guide for Prescribed Fire in Southern Forests. USDA Forest Service.

LIVESTOCK SYSTEMS

Sheep Production

                The cycle for breeding sheep for meat begins in the autumn (Sept – Dec) so that lambs are born when grass is available (Spedding 2007) is the spring. Early lambing from Dec-Mar has advantages such as more rapid weight gain, fewer problems with hot weather and parasites and lambs can be sold without being put to pasture. Later lambing (late March) advantages include fewer building requirements, lower feed costs, higher lamb survival due to better weather and lambs can make the maximum use of the available pasture (Ricketts et al 1993). Some farmers use Creep grazing for their lambs, which is when lambs are allowed to graze fresh, unsoiled areas of younger grass which the ewes don’t have access to (Spedding 2007).

                Some farmers time their lambing for autumn (Sept-Dec) which has advantages such as favourable weather, lower feed and labour requirements, good prices for lambs and the possibility of accelerated breeding. Accelerated breeding is when ewes produce lambs 3 times in 2 years. So they have lambs every 8 months and lambs are weaned by 60 days at the latest so ewe’s can re-breed in 30 days (Ricketts et al 1993).This does mean, however, that ewe’s require additional supplementary feeding as they may be pregnant during times of bad pasture.

                Another method of breeding is oestrus synchronisation. Ewes usually come into heat when the daylight hours become shorter (Sept, Oct, Nov). Their oestrus cycles can be synchronised by introducing them to progesterone hormone treatment for 14 days. Withdrawal of the treatment results in the ewes coming into oestrus within 1-3 days. Ovulation rate and lamb production can change with the seasons.

Table 1. Performance of Rambouillet Ewes Bred During Four Different Seasons in Texas (taken from Ricketts et al 1993)

Breeding Intervals
	Mar 21 – May 2	Jun 21 – Aug 2	Sept 21 – Nov 2	Dec 21 – Jan 1
Percentage
Ovulation rate	106	141	175	152
Lamb production	84	97	127	135*

*Higher lamb production in December is believed to be due to better embryo survival at cooler temperatures.

                Lambs are weaned at 12-16 weeks old. The best females are selected for future breeding and the rest are finished for slaughter. A profitable lamb flocks needs to meet carcase weights. In Britain these range from 12kg to 20kg+ depending on the breed (Anderson Unknown). The farmer needs to assess different selling options such as auction, private sale, direct consignment to the abattoir and auction plus internet based sale. They also need to consider transport costs and compare live weight price (£/head) with carcase weight price (£/kg dressed and skin price). Market specifications are often narrow so lambs sold outside the ideal weight and fat score can lose money (Court et al 2010).

Dairy Cattle Production

                Dairy cattle can be bred in a few ways. 1. The bull can be in with the cows and detect when they are on heat and mate with them unaided by the farmer, 2. The bull can be kept nearby. The farmer detects when the cows are on heat and introduces the bull to them, 3. Artificial insemination. Cows are checked regularly for when they are on heat and are inseminated as soon as possible (Bonnier 2004). In modern dairy farms, cows can be fitted with an electronic tag around one leg. When they enter the milking parlour, a computer detects how far the cow has walked since she was last milked. If she has been walking a lot, then she could be on heat. If her movement has been limited, she could be injured or sick.

Cows calving in the summer months generally produce less milk compared to calving at other times of year. Calves are removed from the mother after a few hours and continue to be fed colostrums for 2-3 days (Gillespie & Flanders 2010). Females are raised for milk production and as replacements for existing stock. Bulls and dairy cows with low milk yields or cows that fail to conceive are fattened up for slaughter (Phillips 2010).

                Prices for milk varies seasonally, usually with lower prices in May and June and higher prices in October to December. There is increase competition from imitation and substitute dairy products such as margarine. There is an increased demand for fluid, low-fat milk, fresh cream, ice-cream and butter. Demand is affected by population, price of dairy products and the price of competing products (Gillespie & Flanders 2010).

Beef Production

                The cow-calf system of beef production is when cows are bred to produce calves, which are sold to cattle feeders who feed them to slaughter weights. Beef cows can be maintained on roughage so can go on land that crops cannot utilise. Cows generally calve in spring to coincide with the best available pasture. The oestrus cycles of the cows can be managed using hormone treatments so they call come in heat at a similar time (Jarrige & Beranger 1992). Artificial insemination is only used in about 3-5% of beef cows in the UK. Famers use the bull to detect oestrus in the cows and breed with them (Ball & Peters 2004). Calves are weaned in autumn and sold, or fed roughage through winter and sold as yearlings. Feeder calves are sold for further growth, yearling feeders are sold for finishing and slaughter. The aim of cattle feeders is to produce slaughter weight cattle in the shortest time possible (Gillespie & Flanders 2010).

                Suckler herds are cows bred to produce calves which suckle all their milk up to weaning at 6-10 months. 30% of cows in the UK are suckler cows, 90% of which are beef-dairy (Jarrige & Beranger 1992) so females are often used to milk production.

Figure 1 – Beef cuts

                Beef is selected on conformation. Animals should produce the maximum amount of high priced cuts such as seen in Figure 1. Loin (1), rib (2), round (3) and rump (4). Cheaper cuts are chuck (5), brisket (6), flank (7), navel (8) and shank (9).

                Slaughter calves are between 3 and 8 months and sold as veal. Beef cattle are usually marketed through terminal markets, auction markets and direct selling. When being taken to market, cattle can shrink so careful management and handling is needed to reduce shrinkage and damage (Gillespie & Flanders 2010).

Summary

               

Many farmers need to manage their animals according to seasons, such as in sheep farming as it is best for lambs to be born in spring when fresh grass arrives and weather conditions are more favourable. This is not such a problem in beef and dairy cattle, as beef cattle can be fed on roughage and on fairly unfertile land. Dairy cattle can be turned out to pasture when there is good grass. 

                Oestrus cycles in cattle and sheep need to be careful managed. Sheep oestrus can be synchronised using progesterone treatment, so the ram can be introduced and mate with all females at a similar time, therefore lambs are all to be born around the same time. Cattle oestrus cycles can be monitored using an electronic tag which records how far the animal walks between each visit to the milking parlour. The bull can then be introduced or the cows can be artificially inseminated. Beef cattle oestrus cycles can also be controlled using hormone treatments. Artificial insemination in beef cows is rare, the bull is usually left to detect when the cows are on heat and mate with them.

                Market requirements for meat vary throughout the year depending on seasons. Meat will reach higher prices at market if it reaches a favourable carcass weight and fat score. Dairy products are in less demand due to imitation products at more favourable prices for the public. Beef can be sold live at market to cattle feeders, who buy calves to feed them and fatten them up to slaughter weight. The main methods of meat sale are auctions and direct sales to other farmers or abattoirs.

References

Anderson J (unknown) Sheep Management Matters No. 8. Planned carcase production. Meat and Livestock Commission.

Ball P.J.H. & Peters A.R. (2004) Reproduction in Cattle 3^rd Edition. Blackwell Publishing Ltd.

Bonnier P, Maas A & Rijks J (2004) Agrodok 14. Dairy Cattle Husbandry. Agromisa Foundation, Wageningen.

Court J, Webb Ware J & Hides S (2010) Sheep Farming for Meat and Wool. CSIRO Publishing.

Gillespie J.R. & Flanders F.B. (2010) Modern Livestock and Poultry Production 8^th Edition. Cengage Learning, Inc.

Jarrige R & Beranger C (1992) World Animal Science .C. Production-system Approach: 5. Beef Cattle Production. Elsevier Science Publishers B.V.

Phillips C.J.C. (2010) Principle of Cattle Production 2^nd Edition. CAB International.

Ricketts G.E, Scoggins R.D, Thomas D.L, Thompson L.H. & Carr T.R. (1993) North Central Regional Extension Publication 240. Management Guidelines for Efficient Sheep Production.

Spedding A (2007) Discovering sheep farming factsheet. Source:www.face-online.orh.uk/resources/factsheets/discovering/sheep.doc