Klop-Toker Kaya, Valdez Jose, Stockwell Michelle, Fardell Loren, Clulow Simon, Clulow John, Mahony Michael
Conservation Biology Research Group, School of Environmental and Life Science, University of Newcastle, Callaghan, 2308, NSW, Australia.
PLoS One. 2016 Jul 27;11(7):e0159143. doi: 10.1371/journal.pone.0159143. eCollection 2016.
Mitigation to offset the impacts of land development is becoming increasingly common, with reintroductions and created habitat programs used as key actions. However, numerous reviews cite high rates of poor success from these programs, and a need for improved monitoring and scientific testing to evaluate outcomes and improve management actions. We conducted extensive monitoring of a released population of endangered green and golden bell frogs, Litoria aurea, within a created habitat, as well as complementary surveys of a surrounding wild population. We then compared differences between the created habitat and natural ponds where extant frogs either bred or didn't breed in order to determine factors that contributed to the breeding failure within the created habitat. We evaluated differences of L. aurea abundance, abundance of other fauna, vegetation, water quality, habitat structure, invasive fish, and disease between the three pond types (created habitat, breeding ponds, non-breeding ponds). We discovered that vegetation and invertebrate diversity were low within the created habitat, potentially reducing energy and nutritional resources required for breeding. Also, a greater proportion of frogs in the created habitat were carrying the chytrid fungal pathogen, Batrachochytrium dendrobatidis, compared to the wild populations. In addition to causing the potentially fatal disease, chytridiomycosis, this pathogen has been shown to reduce reproductive functioning in male L. aurea, and subsequently may have reduced reproductive activities in the created habitat. Conspecific attraction, pond hydrology, and aquatic vegetation may also have had some influence on breeding behaviours, whilst the presence of the invasive mosquitofish, Gambusia holbrooki, and heterospecific tadpoles were unlikely to have deterred L. aurea from breeding within the created habitat. Through the use of scientific testing and monitoring, this study is able to make recommendations for future amphibian breed and release programs, and suggests planting a diversity of plant species to attract invertebrates, creating some permanent ponds, connecting habitat with existing populations, trialling artificial mating calls, and following recommendations to reduce the prevalence of disease within the population.
减轻土地开发影响的缓解措施越来越普遍，重新引入和创建栖息地项目被用作关键行动。然而，众多综述指出这些项目成功率很低，需要改进监测和科学测试以评估结果并改善管理行动。我们对在创建栖息地中放归的濒危绿金铃蛙（Litoria aurea）种群进行了广泛监测，并对周围野生种群进行了补充调查。然后，我们比较了创建栖息地与现存青蛙繁殖或未繁殖的天然池塘之间的差异，以确定导致创建栖息地内繁殖失败的因素。我们评估了三种池塘类型（创建栖息地、繁殖池塘、非繁殖池塘）之间绿金铃蛙的丰度、其他动物的丰度、植被、水质、栖息地结构、入侵鱼类和疾病的差异。我们发现创建栖息地内的植被和无脊椎动物多样性较低，这可能减少了繁殖所需的能量和营养资源。此外，与野生种群相比，创建栖息地中携带蛙壶菌病原体（Batrachochytrium dendrobatidis）的青蛙比例更高。这种病原体除了会引发可能致命的壶菌病外，还被证明会降低雄性绿金铃蛙的生殖功能，进而可能减少创建栖息地内的繁殖活动。同种吸引、池塘水文和水生植被也可能对繁殖行为产生了一些影响，而入侵食蚊鱼（Gambusia holbrooki）和异种蝌蚪的存在不太可能阻止绿金铃蛙在创建栖息地内繁殖。通过科学测试和监测，本研究能够为未来的两栖动物繁殖和放归项目提出建议，并建议种植多种植物物种以吸引无脊椎动物、创建一些永久性池塘、将栖息地与现有种群连接起来、试验人工交配叫声，并遵循相关建议以降低种群内疾病的流行率。
