Presentation is loading. Please wait.

Presentation is loading. Please wait.

1 The Grey Partridge Past, Present and Future. 2 The copyright of this presentation is reserved by the NGO Educational Trust and the individuals and organisations.

Similar presentations

Presentation on theme: "1 The Grey Partridge Past, Present and Future. 2 The copyright of this presentation is reserved by the NGO Educational Trust and the individuals and organisations."— Presentation transcript:

1 1 The Grey Partridge Past, Present and Future

2 2 The copyright of this presentation is reserved by the NGO Educational Trust and the individuals and organisations who have provided the component images. It should not be reproduced in part or as a whole without their permission. © National Gamekeepers Organisation Educational Trust, April 2013 The Grey Partridge Past, Present and Future

3 3 The NGO Educational Trust are particularly indebted to the Game & Wildlife Conservation Trust (G&WCT) for providing much of the material contained in this presentation and also Stephen Tapper and Dick Potts for their help and advice throughout this project. The Trust also wish to thank: - Jacques Hicter for allowing us to use and include his DVD Perdreaux et Quintaux (Partridges and Yields). - The British Ecological Society for allowing us to reproduce three research papers published in the Journal of Applied Ecology We also wish to thank David Mason for providing the majority of the photographs used in this presentation. Acknowledgements

4 4 The Grey Partridge has evolved in the temperate grassland ecosystems of the Asian Steppes in the Northern Hemisphere. Mans early development in agriculture, especially the clearing of woodland and early growth of cereal crops created even more and new favourable habitat and brought about a further increase in numbers The Grey Partridge

5 5 Farming between the Wars Back to the 1930s, when corn was cut with a reaper

6 6...and sheaths of corn stacked in stooks to ripen before threshing Farming between the Wars

7 7 Throughout Europe, Asia and North America (where it was introduced) the Grey Partridge was a prolific species and was the most numerous bird on many arable farms. In the 20th century it became an iconic image of rural Britain with coveys of partridge to be seen in most fields. Iconic Image

8 8 In the years following the second world war there was a dramatic decline in Grey Partridge numbers, not only in Britain but across its full range. This was due to: - a reduction in predator control due to the number of gamekeepers serving and killed during World War 2 - the modernisation and development of intensive farming practice involving the extensive use of pesticides, particularly herbicides. Modern Farming

9 9 Fieldsport Feedback This decline was first noticed, recorded and reported by the shooting organisations. The Grey Partridge was a prolific and popular game bird highly regarded as an exciting quarry species and much prized for its delectable flavour. Over 2 million were shot annually in the UK between the wars and some 25 million shot annually across Europe. At that time it was the most important lowland game bird. Analysis of game bags on major shooting estates enabled a graphical representation of its decline in Britain. Similar declines were recorded across Northern Europe.

10 10 1900191019201930194019501960197019801990 2000 2 4 6 8 10 B a g p e r 1 0 0 h e c t a r e s WWI WWII Game Bag Records Show Decline of the Species

11 11 Population Decline It is estimated that there were more than 1 million breeding pairs in Britain prior to the second World War and this population has now reduced to 65,000 pairs. It is also estimated that in 1953 there were 110 million pairs in the world which had reduced to 25 million by 1985.

12 12 The Grey Partridge decline is clearly a world phenomenon but nowhere is it more significant than in England. Our focus is on Grey Partridge but it also poses the question as to the effect of the same factors on a wide range of other wildlife species, such as butterflies, sharing the same habitat. Is this an indication that all is not well in the British countryside? Meadow BrownTortoiseshellPeacock Global Decline

13 13 Not surprisingly it was game biologists, most notably Dr. G.R. Potts, who were the first to scientifically investigate and demonstrate the reasons for this decline. Much of this early research in Britain was carried out at:- ICI Game Research Station at Fordingbridge then the Game Conservancy Trust, now the Game & Wildlife Conservation Trust currently based at Burgate Manor, Fordingbridge Population Decline

14 14 Britain s first steps in ecology Game biologists were the first to show the consequences of herbicide use for farmland birds. Early work by Dr. D. Middleton, the first director of the Game Research Association funded by Eley, included studies on the % of birds surviving from hatching to adulthood. Doug Middleton The Grey Partridge is now one of the most intensively studied birds in Britain. A summary of partridge research projects is included on the disk & the NGO ET website Three of the most important research papers are also included on the disk & the NGO ET website

15 15 G.R.Potts book The Partridge, Pesticides, Predation and Conservation published by Collins in 1986 was, and still is, regarded as the complete, authoritative gospel An Authoritative Guide

16 16 Professor Jon Hutton is a member of the monitoring group of the United Nations Environment Programme based at Cambridge and he is also Chair of the Sustainable Use Specialist Group. Their role is to evaluate the values of Biodiversity and put authoritative biodiversity knowledge at the centre of decision making. He has pointed out that:- 22 million recreational hunters spend £16 billion per annum (shooting, falconry, angling, etc) gives economical value to land and habitats favourable to wild species which would otherwise be converted to crop lands. Recreational hunting achieves conservation in situations where there are few alternatives. Where it is practiced responsibly in context with good governance recreational hunting is an important tool for conservation. Those linking hunting with conservation need to demonstrate what they are doing and why. Conservation and the Recreational Shooter

17 17 Fieldsport Feedback The appearance of much of the British countryside as we know it today has been largely shaped by hunting, shooting and farming. It was the recreational shooter who first alerted the government to the demise of the grey partridge and they are the body/group most prepared and determined to actively seek a solution. One of the problems in the UK is that few of the government, scientific and wildlife bodies have as much experience or background knowledge as the hunter based organisations. Liaison between both camps is now, thankfully, beginning to improve. It is now generally recognised that the future of the Grey Partridge is closely linked to recreational shooting. If it was made a protected species or game shooting was banned, then most of the finance and conservation management linked to field sports, which is bringing about its current recovery, could disappear overnight.

18 18 Biodiversity Action Plan (BAP) In 1996 the Grey Partridge was identified in Britain as a Biodiversity Action Plan Species and it was the Game Conservancy Trust (now the Game & Wildlife Conservation Trust) who were made the lead partner by the UK government. They are responsible for delivering targets by deadlines Their role is to carry out research, advise, monitor, advocate and demonstrate, best practice and get the research into Government s agri- environment policy.

19 19 Factors involved in Grey Partridge decline in Britain The annual National Game Census, which was initiated by the GCT in 1956, monitors a number of species including the Grey Partridge. Studies in Grey Partridge mortality rate initiated by the GCT looked at deaths recorded at various stages in life cycle/ year :- 1 Egg mortality 2 Nesting Hen mortality 3 Chick mortality 4 Shooting mortality 5 Winter mortality These studies led to insect monitoring in farmland starting in 1969

20 20 National grey partridge Spring pair monitoring Long-term members New members The significant peaks in early 50s, 1960 and mid 70s are thought to be due to particularly good weather in Spring and early Summer. There is an old saying that a wet Ascot week means a bad year for partridges

21 21 A Sussex monitoring site Sussex autumn partridge count - 1970 Shows a family covey (pair + offspring)

22 22 Sussex autumn partridge count - 1994 A Sussex monitoring site Shows a family covey (pair + offspring)

23 23 Sussex autumn partridge count - 2008 Shows a family covey (pair + offspring) A Sussex monitoring site

24 24 Sussex site conclusion The monitoring of Grey Partridge in this Sussex site is a typical example showing a progressive decline from 1970 to 1994 and then on to 2008. However, this site includes a discrete recovery in the east of this region centred on the Norfolk Estate, Arundel. This recovery demonstrates what can be achieved and is testament to the hard work and commitment of the Duke of Norfolk and his team. A summary of this project is included on the disk.

25 25 Population Decline The recorded 80% decline in Grey Partridge is similar in both timing and rate in several Northern European countries. The modernisation of farming spread so quickly that many of the factors involved in the decline were synchronised across much of the Northern hemisphere. Conclusions from studies in Britain may well therefore be relevant elsewhere.

26 26 Main Issues Identified 1.Habitat decline 2.Decline in Gamekeepers Reduction in predator control Habitat and conservation management 3.Increased use of pesticides and herbicide

27 27 Main Issue 1: Habitat Decline Habitat decline; more and more land has been taken into modern intensive farming with larger fields bringing about loss of hedgerows and hedge banks. The introduction of new winter wheat varieties led to a prevalence of Autumn seed drilling. This resulted in a reduction of Winter stubbles and subsequent loss of Winter food for both partridges and songbirds. However G&WCT still estimate that there is potential suitable general habitat for 511,000 pairs of Grey Partridge (8x more than we have actually got).

28 28 Potential habitat within the UK yellow Optimum Land = 36,000 km2 (yellow) Sub-optimum land = 42,000 km2 (green) Present UK population is 65,000 pairs There is a habitat potential of 511,000 pairs.

29 29 Potential Habitat This poses the question why the current population is so low; the current population is 65,000 pairs whereas the estimated habitat potential is 511,000. This shows that habitat may be important but is not the most significant factor.

30 30 Necessary Habitat Improvement Providing year round food for grey partridge Late winter and spring cover Nesting cover Accessible, insect rich habitat for brood rearing

31 31 Habitat Improvement Nesting cover Grey Partridge favour nest sites in grass margins adjacent to hedgerows on banks

32 32 Habitat Improvement Old dead tussocky grass It is the previous years uncut dead grass that provides the best nesting sites

33 33 Habitat Improvement

34 34 Accessible, insect rich habitat next to nesting cover This could be further improved by providing protection from aerial strikes. Habitat Improvement

35 35 The margin flora is unaffected by cropping rotation The headland loss is of little economic significance because this is an area of traditionally poor crop yield and is better utilised for conservation. A 6-metre strip all round a field provides territory for a greater number of partridge pairs than the same area in a single block Habitat Improvement

36 36 A colourful public relations brood rearing mix! However, a 6-metre margin of unsprayed and unfertilised stubble is more important to the Grey Partridge chicks Habitat Improvement

37 37 Over winter food & cover-stubbles Habitat Improvement

38 38 Un-harvested Conservation Headlands This looks good and in the absence of other cover can provide useful shelter from raptors immediately after harvest. However the large single flush of food attracts vermin, particularly rats. Habitat Improvement

39 39 Biennial cover crops such as Kale This can provide vital cover for pairs in Spring Habitat Improvement

40 40 Kale mixes Kale provides good cover and when mixed with different varieties of quinoa, which ripen in sequence, achieves continuous natural food over a greater period of time. Habitat Improvement

41 41 Post harvest auto-cast Kale Gamekeepers continuously experiment to get the most beneficial margin habitat including annually renewing half and leaving half to provide cover. Kale provides good cover but another option is 3 metres of chicory, both reduce sparrow hawk strikes, and then a further 3 metres of wild flower mix sown amongst cereal as a brood mixture providing seeds and insects. The food hopper provides over- winter and spring feeding. The following June it looks like this Habitat Improvement

42 42 Habitat Improvement Summary Provide round the year cover that offers: 1.Protection from predators - especially in late winter & spring 2.Nesting areas 3.Accessible, insect rich areas For further information go to

43 43 Main Issue 2: The Decline of Gamekeeping 1911 1981 Gamekeepers per 1000 hectares >1.6 0.8 - 1.6 0.4 - 0.8 0.2 - 0.4 0.1 - 0.2 <0.1 The 25,000 employed in 1911 has shrunk by 80% Traditionally it was one keeper per thousand acres

44 44 Days of Plenty

45 45 Grey Partridge Predators Fox StoatWeaselRat The fox is the most serious predator, followed by the stoat, rat and weasel. Different predators tend to be more destructive at different times of the year It was always said that to avoid foxes coveys fly out into the middle of fields to jug up for the night – thus leaving no scent trail leading to them

46 46 Grey Partridge Predators The Grey Partridge has a number of winged predators. Amongst these two the carrion crow is the most serious followed by the magpie. MagpieCarrion Crow

47 47 Intra-guild effects on fox Intra-guild predation on the red fox Top predator Numbers reduction/ interference on fox Authority Gamekeeper 83% Tapper et al. (1996) Coyote 86% Sovada et al. (1995) Lynx 41% Helldin et al. (2006) Wolf36% coyoteBerger & Gese (2007) Golden eagleΞ13% dietKorpimaki & Nordstr ö m (2004) Intra-guild predation, in which higher level predators control middle or lower level predators within a food web, is a factor which is reducing in many countries. Historically the red fox population would have been held in check by a number of natural predators. However the wolf, lynx, coyote and golden eagles are no longer present in many countries. It is now a crucial role of the gamekeeper to attempt to restore and keep the balance particularly in the British countryside.

48 48 Predator Control 1.Rifle and scope 2.Shotgun 3.Larsen trap 4.Spring traps used in a tunnel 5.Approved snares 4 3 2 1 5 Tools of the trade

49 49 A rolling landscape of arable, sheep grazing and military training Salisbury Plain Predator Control Experiment

50 50 Salisbury Plain study areas

51 51 Decline in Game Keepers The 25,000 keepers employed in 1911 have reduced by 80% leading to a reduction in predator control In the Salisbury Plain Experiment Grey Partridge numbers on large plots of land were monitored over a 3 year test period. A plot of keepered land with good predator control was compared to a plot with no predator control. At the end of 3 years the predator control variable for the 2 plots was reversed for a further 3 year period.

52 52 Adult males Total birds Bag 53 233 22 32 213 65 Partridge brood counts 1984 The Baseline Year Covey – size related Single male (hen killed?) Adult pair with no offspring (eggs eaten or no chicks survived)

53 53 Adult males Total birds Bag 30 79 1 57 318 27 No control 1987 Predation control Covey – size related Single male (hen killed?) Adult pair with no offspring (eggs eaten or no chicks survived) Partridge brood counts

54 54 Adult males Total birds Bag 49 399 105 29 128 25 Predation control 1990 No control Covey – size related Single male (hen killed?) Adult pair with no offspring (eggs eaten or no chicks survived) Partridge brood counts

55 55 Conclusions Predation control –Increased the production of young grey partridge –August numbers improved 75% annually –Over 3 years this resulted in a 3.5 fold change –Breeding stocks, measured in spring, increased by 35% p.a. –Over 3 years resulted in a 2.6 fold change Salisbury Plain Predator Control Experiment

56 56 Gamekeepers and Conservation Gamekeepers would also be involved in reducing disturbance to breeding partridge, the maintenance of favourable habitat, particularly game crops. Also provision of supplementary feeding particularly in Winter. In Spring many pairs nest close to these feed sites. This may reduce the size of territory resulting in pairs nesting closer together. These activities also benefit a wide range of other species The G&WCT and the NGO believe that wise use of the British countryside rather than protectionism is the most constructive route forward.

57 57 Main Issue 3: Increased use of pesticides and herbicides The development and increased use of Pesticides in an attempt to increase human food production following World War II seems to have been the main trigger that started the Grey Partridge decline. Pesticides, especially herbicides which came into use 20 years earlier than insecticides, break the chick food chain In fact both insecticides and herbicides inhibit insect populations and diversity

58 58 Insect Dependency Red-Leg Partridge and chicksGrey Partridge and chicks The use of pesticides breaks the chick food chain. This is so crucial for the Grey Partridge because the chicks are solely dependant on a plentiful supply of suitable insect species for the first 10 days after hatching before they start to eat seeds. It is interesting that Red Leg partridge chicks start on seeds after only 3 days.

59 59 Crop Spraying

60 60 If you must Spray Avena spp. (wild oats):tri-allate diclofop-methyl difenzoquat flamprop-m-isopropyl Alopecurus mysuroides (black- grass): tri-allate diclofop-methyl HOE 7113-01H Elymus repens (couch):glyphosate Herbicides for selective control of grass weeds in cereal headlands? Farmers must make a profit Spraying is linked to yield Be selective with the insecticides and herbicides you choose

61 61 Breaking the food chain What is clear is that improvements made to chemicals used in modern farming over the past few decades have not brought about the dramatic recovery in Grey Partridge numbers seen in some other species. This may seem surprising because the Grey Partridges potential to bounce back, with brood size numbering up to 14, is enormous. This is because the new chemicals used are not themselves mortally toxic to the Grey Partridge or its chicks but it is that their use in modern farming methodology still has the same significant effect of breaking the crucial early chick nutrition. It will also impact on interaction within the local food web. What is now becoming clear is that other species, such as birds like skylarks and corn buntings, are affected by these same factors.

62 62 Breaking the food chain It would appear that we are not dealing with a contact toxin, a lethal dose for chicks or even an accumulative toxin. Whatever new chemicals are developed and used, if they are effective as herbicides and/or insecticides, they are still collectively likely to break the chicks food chain. Because the timing of their application is critical to the crop it may well also unfortunately be equally critically timed to the life cycle of the Grey Partridge i.e. the first 10 days after the chicks hatch. Reduced and selective pesticide use in response to actual crop problems rather than their use as a blanket preventative safeguard may also be beneficial. Selective timing of the reduced use of such agro-chemicals, if achievable, may yet be a critical long term deciding factor in ensuring the future of the Grey Partridge.

63 63 Chick survival Low input conservation headlands to increase insects Plant Wild Bird seed mixture Dont use summer insecticides on headlands The availability of insect food is crucial. It could be improved by use of one or other of the entry-level stewardship options :

64 64 Chicks Favourite Insects Click here to view a short YouTube video

65 65 Grey partridge chick nutrition Chicks raised with and without insects Animal proteins from insects needed for fledging

66 66 Conservation Headland One solution is to create spray free conservation headlands, by not spraying a 6- metre border around the crop

67 67 Un-Sprayed Conservation Headland It is difficult to get farmers to agree not to spray headlands due to the belief that there is re-infestation by both weeds and insect pests

68 68 Grey Partridge chick survival Conservation headland trials in Norfolk

69 69 Chick survival with conservation headlands Block A (no conservation headlands) Block B (conservation headlands introduced after 2003) 1968-2003 29%31% 2004-2008 27%53% The improvement in survival amounted to an additional 3.6 chicks per brood Two similar adjacent blocks of land, with no conservation headlands, were chosen for a comparative study. The chick survival percentage was established for the period 1968 – 2003 on both sites. In the period 2004 – 2008 Block A was left without conservation headlands but on Block B conservation headlands were established and maintained.

70 70 Research programme for Conservation Headlands Does it work for another game species? Yes it does – and also for song birds PheasantLinnet

71 71 Other benefits to wildlife Wildflowers Butterflies Small mammals Predatory beetles Corn Marigold Field Mouse Predatory BeetleHedge Brown Prickly Poppy Research programme for Conservation Headlands

72 72 Other Factors There are clearly a number of issues involved in the Grey Partridge decline and it may well be a quite complex interaction of factors. Previously present factors may well have become more significant as the decline reached critical thresholds. Some think that factors such as predation by protected species inhibit any national recovery from the low population count that currently exist in many areas.

73 73 Protected Predators While everyone is pleased to see a recovery in the population of rare and protected species the decision makers need to recognise that if these species are predators there is an ecological price to pay. Red KiteHen HarrierMarsh Harrier

74 74 While such species benefit from this protection and their populations increase beyond natural limits they start to impact on the vulnerable prey species. BuzzardBadger Protected Predators

75 75 It is possible that a national Grey Partridge recovery may be handicapped by current increased populations of their natural predators. Sparrowhawk GoshawkFreshly Killed Grey Partridge Goshawk on Pheasant Protected Predators

76 76 Population Dynamics Model Predation loss depends on control of nest predators Chick survival depends on herbicides and insecticides Winter loss depends on hedgerows, spring cover and feed hoppers Start Predator Control Herbicide Use Spring Cover + Feed Hoppers Breeding Stock Autumn Count Number Shot Winter Loss Increased hen mortality &egg loss Decreased hen mortality &egg loss Increased chick survival Reduced Winter loss Reduced chick survival Increased Winter loss Shooting policy dependant on Autumn count DECREASING POPULATION INCREASING POPULATION Yes No Yes No Yes No

77 77 The Royston Project The Game & Wildlife Conservation Trust have put forward a protocol to save the Grey Partridge as a national species. It is based on an improvement in the number of controllable factors and has been put into practice at its test site at Royston.

78 78 Royston Protocol 1.Provide good Winter and Spring cover crops for shelter, hiding places and food. 2.Supplementary winter feeding strategically placed hoppers near cover crops and nesting sites. Also select and strategically plant insect rich habitat. 3.Good nesting sites –hedgerows and beetle banks- particularly those close to supplementary feeding sites. 4.Chick survival is increased by moderated use of selected herbicides and insecticides and provision of 6-metre unsprayed field margins

79 79 5.Intensive Traditional Gamekeeping to provide: habitat maintenance- high level of liaison with landowners and/or tenant farmers for the considerations listed in 1 4 are essential but expensive consequences of the decision making necessary to give Grey Partridge population numbers any chance of recovery predator control- also expensive and time consuming requiring an experienced, skilled person to target identified species The particularly well keepered Royston project loses 40% of sitting hens but without intensive game keeping it could be 80% or higher 6.Census numbers, at critical phases, help to monitor the status of the Grey Partridge within the Biodiversity Action Plan Royston Protocol

80 80 7. Control the practice of Grey Partridge shooting - limit to harvesting the surplus. Until stocks recover dont shoot grey partridges 1.Only those conserving good stocks (more than 20 per 250 acres) should consider shooting 2.Never shoot greys after December 3.Never shoot partridges that are in pairs 4.Take precautions not to shoot greys when shooting redleg partridges Royston Protocol

81 81 Grey partridge pairs – Spring 2002 2.9 pairs / sq. km 20 Pairs total The Royston Project

82 82 Grey partridge pairs – Spring 2007 18.4 pairs / 184 pairs total 2007 The Royston Project

83 83 Spring pairs at Royston 200220032004200520062007 Target Year 0 5 10 15 20 Spring pairs / 100 ha Reference area Demonstration area 0107 Predicted31185 Actual 19 184 The Royston Project

84 84 Number of game birds counted in autumn (Birds / Grey partridgeRed-legged partridgePheasant AutumnDensity Young: Old Ratio Density Young: Old Ratio Number 20017.60.615.70.366 200228. 200339.12.943.92.2432 200453.42.843.91.2537 200560.81.958.40.9612 200687.82.677.51.5522 The Royston Project

85 85 Number of brown hares counted in winter Year Hares DemoRef Spring 20023963 Winter 20029483 Winter 200315957 Winter 200417975 Winter 200518593 Winter 2006216137 The Royston Project

86 86 Songbirds at Royston Song Thrush Chaffinch GoldfinchGreenfinch The Royston Project

87 87 Jacques Hicter Project Jacques Hicter, a shooting farmer from northern France, has also achieved remarkable results from a total commitment to the future of the Grey Partridge, the balance of natural ecology and modern farming methodology. His activities feature in a DVD, sponsored by Syngenta, which is included on the disk and can be viewed on the NGO ET YouTube Channel. Click here to view now Click here to view now

88 88 Jacques Hicter Project - Population Growth The graph shows the population recorded at Jacques Hicters two farms, situated 20kms apart. He has achieved similar success at both sites. 1980199020002010 0 20 40 60 80 100 pairs per 100ha The sharp decline in 2007 and 2008 is almost certainly due to adverse weather conditions

89 89 Grey Partridge - Conclusions The overall impression in 2008 is that a Grey Partridge recovery will be hard earned. There is unlikely to be any short term spectacular bounce back. The G&WCT have identified a number of key factors in the original demise which may all need to be countered and they have produced recommendations in a recovery document. Even in the G&WCT project areas where a recovery is in progress it has not yet been demonstrated that a similar recovery is possible on a wide range of other soil types or that the population will stand even a controlled shooting strategy.

90 90 What has been demonstrated by the G&WCT at Royston, Jacques Hicter in Northern France and more recently the Norfolk Estate Project, is that with passion and complete commitment to the future of the Grey Partridge a local/discrete recovery can be achieved. Grey Partridge - Conclusions

91 91 However those are very intensive and expensive projects and, at present, there seems little evidence that a general species recovery is possible without similar support. The government stewardship scheme, as far as the Grey Partridge is concerned, is probably no more than a small step in the right direction. Dick Potts believes it will be impossible to achieve recovery targets without the crucial role of the gamekeeper. Grey Partridge - Conclusions

92 92 Further Documents on the CD & Website Jacques Hicter video – Perdreaux et Quintaux (Partridges and Yields) G&WCT –Conserving the Grey Partridge –Insect population graphs (1970 – 2005) –How to identify grey partridges –Chick food favourites –Environmental Stewardship: Making the most for grey partridges –Late winter and spring feeding of pheasants and partridges –Providing nesting cover for wild grey partridges –Providing brood-rearing cover for wild grey partridges –Providing winter cover and food for wild grey partridges –Restoring wild grey partridges to your farm –Using predation control to increase wild grey partridge numbers –Summary of research projects British Ecological Society published research papers –Pesticide Use on Cereals and the Survival of Grey Partridge Chicks: A Field Experiment Author(s): M. R. W. Rands –Effect of Hedgerow Characteristics on Partridge Breeding Densities Author(s): M. R. W. Rands –The Effect of an Experimental Reduction in Predation Pressure on the Breeding Success and Population Density of Grey Partridges Perdix perdix Author(s): S. C. Tapper, G. R. Potts, M. H. Brockless Dick Potts – Norfolk Estate Project review

93 93 For further information regarding any aspects of this presentation please contact: Brian Hayes NGO Educational Trust PO Box 3360 Stourbridge West Midlands DY7 5YG : 01384 221308 NGO EDUCATIONAL TRUST CONTACT DETAILS

Download ppt "1 The Grey Partridge Past, Present and Future. 2 The copyright of this presentation is reserved by the NGO Educational Trust and the individuals and organisations."

Similar presentations

Ads by Google