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Effective Management Tool (effective + management_tool)
Selected AbstractsDo voles make agricultural habitat attractive to Montagu's Harrier Circus pygargus?IBIS, Issue 3 2007BEN J. KOKS Loss and degradation of habitat threatens many bird populations. Recent rural land-use changes in the Netherlands have led to a shift in habitat use by breeding Montagu's Harriers Circus pygargus. Since the 1990s, unprecedented numbers of this species have bred in farmland compared with numbers in natural habitat. Destruction of nests by agricultural operations, however, compromises breeding success. Between 1992 and 2005, the number of breeding pairs in the northeastern Netherlands was positively, though weakly, correlated with previous-year estimated abundance of voles, mostly Microtus arvalis. In good vole years, the onset of laying was earlier and mean clutch size was larger. Vole abundance was relatively higher in set-aside land and in high and dense vegetation. We suggest that agri-environmental schemes aimed at increasing the availability of voles in agricultural breeding areas may be an effective management tool for the conservation of Montagu's Harriers in the northeastern Netherlands. [source] Does culling predatory gulls enhance the productivity of breeding common terns?JOURNAL OF APPLIED ECOLOGY, Issue 1 2001Guillemette Magella Summary 1,Large gulls Larus spp. are voracious predators of eggs and chicks of other colonial birds and may threaten rare or endangered species. In this study we tested the effectiveness of removing individual predatory gulls as a management technique for enhancing the productivity of common terns Sterna hirundo nesting in Carleton, Québec, Canada. 2,The productivity and fate of common tern chicks were assessed by following ringed individuals from hatching to fledging during three breeding seasons (1993,95). Concurrently, predation and consumption rates of all predatory gulls were measured before and after the culling started. The culling programme was conducted serially in 1994 by removing the most important predator first until all predators were removed. 3,The rate of chick disappearance was lower and the life span of tern broods was higher in 1994 when the culling was conducted, compared with 1993 and 1995. As a result, the productivity of the tern colony was zero in 1993 and 1995, but positive in 1994 (0·33 chicks pair,1). Measurements of chick mass in 1993 and 1994 showed that growth was normal, indicating that poor feeding conditions or disease were not the cause of chick disappearance. 4,Average predation rates for 1993 (23·3 chicks day,1) and 1995 (14·8 chicks day,1) equated to 61% and 66% of available chicks being taken by gulls, respectively. The predation rate before the culling started in 1994 was similar to 1993 and 1995, with 15·9 chicks day,1, but dropped to 5·1 chicks day,1 after the first gull was shot, and decreased to zero once all predatory gulls were removed. Only five individual predatory gulls were identified during the cull. 5,Predation rates differed markedly amongst specialist predatory gulls, with one individual accounting for 85% of all successful attempts made during the baseline period. Once that gull was removed, the remaining predators increased their predation rate in a manner suggestive of a despotic system. Observations conducted in 1995 showed that the predation rate was almost zero at the beginning of the season but increased dramatically later in the summer, with two gulls together making about 60% of the captures. 6,It is concluded that culling predatory gulls can be an effective management tool to enhance productivity in sensitive or endangered species. However, our data suggest that such culling would need to be repeated each year in order to protect a sensitive species over consecutive years. [source] Effect of floating nest platforms on the breeding performance of Black TernsJOURNAL OF FIELD ORNITHOLOGY, Issue 2 2006David A. Shealer ABSTRACT In 2003 and 2004, we placed 41 floating nest platforms on Grassy Lake in southeastern Wisconsin (USA) to test the hypothesis that reproductive success of Black Terns (Chlidonias niger) is limited by the quality of suitable nesting habitat. Extreme differences in water levels between these 2 yr provided a natural experiment to evaluate the effectiveness of the nest platforms during a drought year (2003) when natural nesting substrate was abundant, and a flood year (2004) when natural substrate was limited during the peak nesting period. Terns nested on 27 of 41 (66%) of the platforms in 2003 and 26 of 41 (63%) in 2004. No difference in the occupancy rate of platforms and natural nests was evident in 2003, but the pattern of clutch initiations early in the season in 2004 indicated that platforms were preferred over natural substrates. In 2003, nest survival rates did not differ between nests placed on platforms and those placed on natural substrates, but platform nests had significantly higher hatching success and nest survival rates in 2004. Both the Kaplan-Meier and Apparent Nest Success methods of calculating nest survival provided similar estimates. In both years, eggs laid on platforms were significantly larger than those laid on natural substrates, suggesting that platforms were occupied by high-quality birds. Our study indicates that floating nest platforms can be an effective management tool to enhance nesting habitat for Black Terns and other aquatic birds that construct floating nests, primarily because platforms provide nest sites when natural sites are not available due to flooding. Nest platforms also may be useful for addressing questions concerning habitat selection and parental quality. SINOPSIS De 2003-2004 colocamos 41 plataformas flotantes para poner aprueba la hipótesis que el éxito reproductivo de la gaviota Chlidonias níger, esta limitado por la calidad y lo apropiado del hábitat de anidamiento. El estudio se llevó a cabo en el Grassy Lake, Wisconsin. Extremos (bajos y altos) en los niveles de agua, causados por sequía (2203) y fuertes lluvias (2004) proveyeron el escenario adecuado para evaluar la efectividad de las plataformas. Las gaviotas anidaron en 27 (66%) de las 41 plataformas en el 2003 y en 26 (63%) de las 41 en el 2004. No se encontraron diferencias en la tasa de uso de las plataformas y áreas naturales en el 2003, pero el inicio de las camadas temprano en la temporada durante el 2004, dieron a indicar que las plataformas fueron preferidas a los lugares naturales. Durante el 2003, no hubo diferencia en la tasa de supervivencia de nidos en plataformas y o en áreas naturales. Sin embargo, durante el 2004 el éxito de eclosionamiento, de los nidos y la supervivencia fue mas alto en las plataformas. Tanto el método Kaplan-Meier como el "Aparente Éxito de Anidamiento", utilizados para calcular la supervivencia de los nidos, ofrecieron resultados similares. En ambos años el tamaño de los huevos fue mayor en las plataformas que en áreas naturales, lo que implica que las primeras fueron utilizadas por aves sumamente vigorosas o de alta calidad. El estudio indica que las plataformas flotantes pueden ser una herramienta de manejo adecuada para mejorar el hábitat de anidamiento de la gaviota estudiada, al igual que otras aves que construyen nidos flotantes. Las plataformas proveen de lugares de anidamientos cuando no hay disponible lugares naturales debido a inundaciones. Las plataformas de anidamiento muy bien pudieran proveer de información útil con respecto a la selección de hábitat y la calidad del cuidado parental. [source] Internationalisation, Diversity and the Humanities Curriculum: Cosmopolitanism and Multiculturalism RevisitedJOURNAL OF PHILOSOPHY OF EDUCATION, Issue 3 2007JAMES DONALD This article stages a dialogue between cosmopolitanism and multiculturalism in order to think through what is at stake in demands that universities should produce graduates who are sensitive to social diversity and attuned to the contemporary realities of globalisation. The argument is that, although ,graduate attributes' are no doubt an effective management tool in a massified higher education system, they can also be used to focus attention on what dispositions it is reasonable and desirable to expect graduates to develop. The arguments about cosmopolitanism of Jeremy Waldron and Martha Nussbaum are considered. [source] Attracting endangered species to ,safe' habitats: responses of fairy terns to decoysANIMAL CONSERVATION, Issue 4 2001D. S. Jeffries The New Zealand fairy tern (Sterna nereis davisae) is considered an endangered subspecies. The aims of this study were to quantify fairy tern responses to decoys and sound recordings and determine the viability of decoys as a technique for re-establishment of this species in protected habitat. Sixteen decoy trials were conducted in an area suitable for nesting from 9 September to 2 October 1999 at Papakanui Spit, New Zealand (36°26,S, 174°13,E). The decoy models were effective in attracting fairy terns to a specific area. There was a significant effect due to decoys with >80% of landing episodes occurring in the decoy plots. There was no effect due to individual plots. A planned contrast between decoys with and without recordings showed no significant difference. The behaviour of the fairy terns towards the decoys paralleled live tern interactions, e.g., erect postures, one aggressive response and a possible courtship feeding. Fairy terns appear to be less social than other members of the Laridae family (although their population numbers make the level of gregariousness difficult to determine). Despite low numbers, the response to the decoys was highly significant. We suggest that decoy techniques could be used as a simple and effective management tool for a wide range of group-living species. Such techniques will become particularly important as the availability of suitable habitat declines owing to anthropogenic effects. Finally, regardless of whether the attraction of fairy terns towards these decoys encourages residence and nesting in this area, the effectiveness of attracting terns to a specific location results in a safe and efficient means of trapping adults away from the nest and/or outside the breeding season. [source] Improving assessments of marine protected areasAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2010Joachim Claudet Abstract 1.The use of experimental design and statistical analysis to evaluate the effects of marine protected areas (MPAs) is increasingly popular throughout the world. 2.However, in looking at historical approaches to MPA evaluations, flaws were identified in the execution of theoretically correct designs, as well as disconnects between the stated objectives of MPAs and those of assessment studies. 3.MPA assessments can be improved by: (1) considering the enforcement/compliance level; (2) linking explicitly the choice of indicator(s) to the MPA objectives; (3) accounting for habitat structure; (4) taking into account the age and size of the MPA; and (5) quantifying the fishing pressure outside the MPA (including possible displacement effects). 4.Neglecting social factors, using inappropriate indicators, and/or ignoring relevant covariates, carries the risk of having MPAs dismissed as an effective management tool. Societal expectations are strong that MPAs will confer benefits, and thus assessment studies need to be progressively improved using new methodologies and the best available scientific evidence. Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||