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00012 Fange von Habichten (Accipiter gentilis) im Wurzacher Ried: Kritische Fragen zu einem behordlich genehmigten Wiedereinburgerungsprojekt (Goshawk (Accipiter gentilis) trapping in the nature reserve Wurzacher Ried: critical questions on a black grouse (Tetrao tetrix) reintroduction project)
212
Selected abstracts
as habitat islands. Many patches axe severely damaged by feral animals, weed invasion and contemporary fire regimes. This paper documents the status of an endangered palm, Ptychosperma bleeseri, which occurs within a narrow geographical range in seven rainforest patches. The species does not appear to occupy all suitable habitat available at either a regional scale or within single rainforest patches. Evidence, based on demographic surveys, is presented for the current decline of P. bleeseri populations. Possible causes for this decline include the tmpacts of wildfire and feral animal activity. Recommendations for a recovery plan include fencing, fire protection and public education. -from Authors 94Z/00008 Environmental and historical factors limiting the distribution of r a r e forest grasses in south Sweden J. Brunet, Forest Ecology & Management, 61(3-4), 1993, pp 263-275. The distribution of Hordelymus europaeus, Festuca altissima, Bromus benekenii and Bromus ramosus in Skane is studied in respect to both soil acidity and factors related to former land use. Bromus ramosus seems to be limited primarily by a low soil pH, but the rarity of the grasses compared with other forest species with a similar range in respect to soil pH may be attributed to former land use. The rare forest grasses are restricted to estate beech forests with long continuity. This could be due to a combination of low colonising ability and sensitivity to coppice/wooded meadow management or severe grazing. With a low colonising ability of the rare grasses, the existing populations probably are relics of an originally wider distribution. Conservation of the existing pattern of deciduous forest and management without large clear feilings may be necessary to ensure survival of such species. -from Author 94Z/00009 Management of the exploitation of the lugworm Arenicola marina and the r a g w o r m Nereis virens (Polychaeta) in conservation a r e a s P. L W. Olive, Aquatic Conservation, 3(1), 1993, pp 1-24. Two case studies axe presented describing the population dynamics of i ) Arenicola marina in the Lindisfarne nature reserve, and 2) Nereis virens in the Menai Strait both in conservation areas. Populations of A. marina are subject to marked annual cycles in number and fresh weight. This case illustrates the response of the population to substantial overexploitation leading to a population crash. With the introduction of restrictive legzslation the population was re-established by recruitment of adults from nei/~hbouring unexploited populations. The N. virens population was dominated by large old individuals; it did not represent a sustainable resource in contrast with populations of the same species in other locations. -from Author 94Z/00010 Rapid human-induced evolution of insecthost associations M. C. Singer, C. D. Thomas & C. Parmesan, Nature, 366(6456), 1993, pp.681-683. Rapid evolution of host association is now occurring independently in two populations of the host-specialist butterfly Euphydryas editha, each of which has recently incorporated a novel host species into its diet. The reasons for these episodes of rapid evolution lie in human land use practices: logging in one case and cattle ranching in the other. At both sites, the proportion of insects preferring the novel host has increased, in one case clearly because of genetic changes in the insect population. This process is now starting to generate insects that refuse to accept their ancestral host, foreshadowing a new problem in conservation biology. By adapting genetically to human-induced changes in their habitat, the insects risk becoming dependent on continuation of the same practices. This is a serious risk, because human cultural evolution can be even faster than the rapid genetic adaptation that the insects can evidently achieve. -from Authors 94Z/00011 The decline of the c o r n c r a k e Crex crex in Britain and Ireland in relation to habitat change R . E . Green & T. J. Stowe, Journal of Applied Ecology, 30(4), 1993, pp 689-695.
Censuses of singing male comcrakes on agricultural land in seven sample areas of Britain and Ireland in 1988 and 1991 indicated that a century-long decline in numbers was continuing. Areas differed in the magnitude of the population change during the 3-yr period. Changes ranged from a 4% increase to a 70% decrease. Changes in comcrake numbers were better explained by the habitat suitability index than by any of the individual vegetation cover variables used in its calculation. Declines in comerake numbers were generally associated with reductions in the area of hay-meadows, but increases in short pasture and grassland dominated by Juncus sp.p. also contributed to declines in comcrake habitat suitability in some areas. -from Authors 94Z/00012 Fange von Habichten (Accipiter gentilis) im W u r z a c h e r Ried: Kritische F r a g e n zu einem behordlich genehmigten Wiedereinburg.erungsprojekt (Goshawk (Ac¢~iter gentilis) t r a p p i n g m the n a t u r e reserve W u r z a c h e r Ried: critical questions on a black grouse (Tetrao tetrix) reintroduction project) G. Dobler & K. Siedle, Journal fur Ornithologie, 134(2), 1993, pp 165-171. A black grouse reintroduction project was established in 1978 in the Wurzacher Ried, SW Germany. Since the beginning of this project the staff had a licence to catch, ring and to release but not to kill goshawks. Results however, indicate that most of the goshawks caught in the project may not have been released but illegally killed by the project staff. -from English summary 94Z/00013 Estimating the impact of past persecution and habitat changes on the numbers of b a d g e r s Meles meles in Britain P. Reason, S. Harris & P. Cresswell, Mammal Review, 23(1), 1993, pp 1-15. The current British badger pop.ulation was estimated to be 41 894 + 4404 social groups; if the effects of past persecution were eliminated, the population could be 43 437 + 4731 social groups, an increase of 3.7%. Most of this increase relates to persecution in Norfolk and Suffolk last century. In Britain the badger population is largely confined to areas which are intensively managed, and numbers and distribution of badgers reflect patterns of agricultural activity. However, over-intensive use of the landscape is detrimental to badger numbers. A number of habitat features favourable to badgers were identified; l-kin squares that contained five or more such features had significantly higher mean badger densities. If all the l-kin squares were managed to include five or more of the habitat features favoured by badgers, and the effects of Persecution were eliminated, the badger population could be 58 284 ± 5640 social groups, an increase of 39%. Absence of semi-natural broadleaved woodlands in a l-kin square had the greatest effect in reducing badger numbers, and tree-planting schemes may be beneficial in providing potential new sett sites. However, badgers axe poor colonlsts, and the construction of artificial sells and the translocation of displaced social groups of badgers will greatly facilitate the colonization process. -from Authors
Regional NATURE CONSERVATION REGIONAL
:
94Z/00014 Making room in the Ark: the Endangered Species Act and the Columbia River Basin J. M. Volkman, Environment, 34(4), 1992, pp 18-20,37 -43. Examines the US Pacific Northwest's attempts to work with the Endangered S~pecies Act in managing the natural resources of the regxon. The history of hydroelectric development on the Columbia River, its effects (particulaxly on fish stocks) and the subsequent successes in 'rebuilding' species are outlined. -M.Amos
Selected abstracts
as habitat islands. Many patches axe severely damaged by feral animals, weed invasion and contemporary fire regimes. This paper documents the status of an endangered palm, Ptychosperma bleeseri, which occurs within a narrow geographical range in seven rainforest patches. The species does not appear to occupy all suitable habitat available at either a regional scale or within single rainforest patches. Evidence, based on demographic surveys, is presented for the current decline of P. bleeseri populations. Possible causes for this decline include the tmpacts of wildfire and feral animal activity. Recommendations for a recovery plan include fencing, fire protection and public education. -from Authors 94Z/00008 Environmental and historical factors limiting the distribution of r a r e forest grasses in south Sweden J. Brunet, Forest Ecology & Management, 61(3-4), 1993, pp 263-275. The distribution of Hordelymus europaeus, Festuca altissima, Bromus benekenii and Bromus ramosus in Skane is studied in respect to both soil acidity and factors related to former land use. Bromus ramosus seems to be limited primarily by a low soil pH, but the rarity of the grasses compared with other forest species with a similar range in respect to soil pH may be attributed to former land use. The rare forest grasses are restricted to estate beech forests with long continuity. This could be due to a combination of low colonising ability and sensitivity to coppice/wooded meadow management or severe grazing. With a low colonising ability of the rare grasses, the existing populations probably are relics of an originally wider distribution. Conservation of the existing pattern of deciduous forest and management without large clear feilings may be necessary to ensure survival of such species. -from Author 94Z/00009 Management of the exploitation of the lugworm Arenicola marina and the r a g w o r m Nereis virens (Polychaeta) in conservation a r e a s P. L W. Olive, Aquatic Conservation, 3(1), 1993, pp 1-24. Two case studies axe presented describing the population dynamics of i ) Arenicola marina in the Lindisfarne nature reserve, and 2) Nereis virens in the Menai Strait both in conservation areas. Populations of A. marina are subject to marked annual cycles in number and fresh weight. This case illustrates the response of the population to substantial overexploitation leading to a population crash. With the introduction of restrictive legzslation the population was re-established by recruitment of adults from nei/~hbouring unexploited populations. The N. virens population was dominated by large old individuals; it did not represent a sustainable resource in contrast with populations of the same species in other locations. -from Author 94Z/00010 Rapid human-induced evolution of insecthost associations M. C. Singer, C. D. Thomas & C. Parmesan, Nature, 366(6456), 1993, pp.681-683. Rapid evolution of host association is now occurring independently in two populations of the host-specialist butterfly Euphydryas editha, each of which has recently incorporated a novel host species into its diet. The reasons for these episodes of rapid evolution lie in human land use practices: logging in one case and cattle ranching in the other. At both sites, the proportion of insects preferring the novel host has increased, in one case clearly because of genetic changes in the insect population. This process is now starting to generate insects that refuse to accept their ancestral host, foreshadowing a new problem in conservation biology. By adapting genetically to human-induced changes in their habitat, the insects risk becoming dependent on continuation of the same practices. This is a serious risk, because human cultural evolution can be even faster than the rapid genetic adaptation that the insects can evidently achieve. -from Authors 94Z/00011 The decline of the c o r n c r a k e Crex crex in Britain and Ireland in relation to habitat change R . E . Green & T. J. Stowe, Journal of Applied Ecology, 30(4), 1993, pp 689-695.
Censuses of singing male comcrakes on agricultural land in seven sample areas of Britain and Ireland in 1988 and 1991 indicated that a century-long decline in numbers was continuing. Areas differed in the magnitude of the population change during the 3-yr period. Changes ranged from a 4% increase to a 70% decrease. Changes in comcrake numbers were better explained by the habitat suitability index than by any of the individual vegetation cover variables used in its calculation. Declines in comerake numbers were generally associated with reductions in the area of hay-meadows, but increases in short pasture and grassland dominated by Juncus sp.p. also contributed to declines in comcrake habitat suitability in some areas. -from Authors 94Z/00012 Fange von Habichten (Accipiter gentilis) im W u r z a c h e r Ried: Kritische F r a g e n zu einem behordlich genehmigten Wiedereinburg.erungsprojekt (Goshawk (Ac¢~iter gentilis) t r a p p i n g m the n a t u r e reserve W u r z a c h e r Ried: critical questions on a black grouse (Tetrao tetrix) reintroduction project) G. Dobler & K. Siedle, Journal fur Ornithologie, 134(2), 1993, pp 165-171. A black grouse reintroduction project was established in 1978 in the Wurzacher Ried, SW Germany. Since the beginning of this project the staff had a licence to catch, ring and to release but not to kill goshawks. Results however, indicate that most of the goshawks caught in the project may not have been released but illegally killed by the project staff. -from English summary 94Z/00013 Estimating the impact of past persecution and habitat changes on the numbers of b a d g e r s Meles meles in Britain P. Reason, S. Harris & P. Cresswell, Mammal Review, 23(1), 1993, pp 1-15. The current British badger pop.ulation was estimated to be 41 894 + 4404 social groups; if the effects of past persecution were eliminated, the population could be 43 437 + 4731 social groups, an increase of 3.7%. Most of this increase relates to persecution in Norfolk and Suffolk last century. In Britain the badger population is largely confined to areas which are intensively managed, and numbers and distribution of badgers reflect patterns of agricultural activity. However, over-intensive use of the landscape is detrimental to badger numbers. A number of habitat features favourable to badgers were identified; l-kin squares that contained five or more such features had significantly higher mean badger densities. If all the l-kin squares were managed to include five or more of the habitat features favoured by badgers, and the effects of Persecution were eliminated, the badger population could be 58 284 ± 5640 social groups, an increase of 39%. Absence of semi-natural broadleaved woodlands in a l-kin square had the greatest effect in reducing badger numbers, and tree-planting schemes may be beneficial in providing potential new sett sites. However, badgers axe poor colonlsts, and the construction of artificial sells and the translocation of displaced social groups of badgers will greatly facilitate the colonization process. -from Authors
Regional NATURE CONSERVATION REGIONAL
:
94Z/00014 Making room in the Ark: the Endangered Species Act and the Columbia River Basin J. M. Volkman, Environment, 34(4), 1992, pp 18-20,37 -43. Examines the US Pacific Northwest's attempts to work with the Endangered S~pecies Act in managing the natural resources of the regxon. The history of hydroelectric development on the Columbia River, its effects (particulaxly on fish stocks) and the subsequent successes in 'rebuilding' species are outlined. -M.Amos