Organising pest control by contract

Abstract

The Otago Regional Council uses contractors for control of both possums and rabbits. There is now a much greater emphasis on involving farmers in control work.

In Central Otago, rabbit poisoning operations are carried out under negotiated contracts; landholders provide much of the labour, and Council staff the 1080 and job supervision. This year we are trying a pilot programme for possum control, under which the Council will buy the skins and pay a bonus if a 75% reduction in possum numbers is achieved over a defined area in a certain time.

This paper discusses the details of the various contracts and the practical changes made to improve the job management programme.     

Tetranucleotide microsatellites in the gecko Oedura reticulata isolated from an enriched library

Ten tetranucleotide microsatellite loci were isolated from an enriched library for the gecko Oedura reticulata. The species is endemic to the southwest of Western Australia, known to be a habitat specialist, and exposed to severe habitat fragmentation in the Western Australian wheatbelt. These highly polymorphic markers (two to 25 alleles) will facilitate the population genetic analyses of this species. In particular, they will enable estimates of gene flow between remnant populations — a critical element in assessing extinction dynamics in fragmented populations.     

北京市三个区域食肉类动物食性的比较分析

为了解北京地区捕食性动物的生存竞争关系,于2002年采用样线法收集北京松山、云蒙山、雾灵山3个区域的食肉动物粪便样品85份,并以食物残留物出现频率法进行了食性分析。粪样主要属于犬科的貉和赤狐、鼬科的黄鼬和猪獾、猫科的豹猫。粪样内容物的鉴定发现,此类动物的食物构成以小型哺乳类为主,鼠类的出现频率为82.4%,植物的出现率(54.1%)列为第二位,鸟类的出现率为31.8%,大型猎物的出现率仅为8.3%。犬科动物赤狐和貉的食物构成以棕背(50%)、植物(42.9%)和鼠科动物(40.5%)为主;猫科豹猫的食物构成中植物的出现率为72.4%,其次为鸟类(62.1%)和鼠科动物(48.3%),在生态旅游开发强度较大的区域塑料制品的出现率较高。通过对犬科动物和豹猫的食物生态位重叠度和生态位宽度的比较,讨论了捕食性动物的共存与竞争关系。     

大壁虎两种群的求偶鸣叫变异

大壁虎Gekko gecko俗称蛤蚧,可分为黑蛤蚧和红蛤蚧.黑蛤蚧主要分布在中国的广东、广西和越南的东北部,而红蛤蚧则主要分布在东南亚地区,包括越南南部、老挝、泰国等.本文对这两种蛤蚧种群的求偶鸣叫进行了定性和定量研究.经比较分析结果表明这两个种群蛤蚧的求偶鸣叫声学特征存在明显差异.大壁虎的求偶鸣叫由一系列的音节组成,可分为3段:第一段由0～5个脉冲串组成,每个脉冲串含多个脉冲(7～10);第二段由4～10个双音节组成;第三段由1～3个单音节组成,只有红蛤蚧的求偶鸣叫具有第三段.此外,黑蛤蚧和红蛤蚧的求偶鸣叫差异也表现在第二段,即双音节的结构上.黑蛤蚧的双音节呈现出复杂的频率调节模式,且第一音节和第二音节之间有明显的沉默间隔.红蛤蚧的求偶鸣叫很少或基本没有频率调节,第一音节和第二音节之间没有沉默间隔.结合这两种蛤蚧在形态、染色体和基因结构方面的显著差异,推测传统认为的大壁虎可能由两个不同的物种以及一个亚种组成.     

Step on it: can footprints from tracking tunnels be used to identify lizard species?

There are few effective or efficient established methods for monitoring cryptic herpetofauna. Footprint tracking tunnels are routinely used to index small mammal populations, but also have potential for monitoring herpetofauna. We evaluated the utility of tracking tunnels for identification of New Zealand lizards using captive- and wild-sourced animals (four skink and eight gecko species). All skink prints that we obtained were indistinct or obscure, but we obtained relatively clear, measurable prints for all gecko species. We found that identification to species level was possible for the two gecko species for which we had a large sample—Naultinus gemmeus and Woodworthia ‘Otago large’—using linear discriminant analysis (the best model correctly assigned 96.1% of individuals). Our findings suggest that footprints from tracking tunnels may be used to distinguish between species of geckos. Additional research is needed to assess the ability to further discriminate intra- and inter-genera lizard footprints from tracking tunnels, and the utility of the technique for surveying and monitoring lizard populations.     

Did organochlorine pesticide use cause declines in Mauritian forest birds?

We examine the hypothesis that organochlorine pesticide use in the 1950s and 1960s caused population declines and local extinctions in two endemic Mauritian birds, the Mauritius kestrel, Falco punctatus, and Mauritius cuckoo-shrike, Coracina typica. This hypothesis was suggested in the 1980s but is dismissed by authorities in Mauritius. The declines and subsequent increases in the populations and range areas of both species, the timing and location of the use of organochlorines for malaria control and in food crop production, the diets of the species, and the known mechanisms for transfer of organochlorine residues into organisms are all consistent with the hypothesis. No alternative explanation can at present account for these population changes. Organochlorine pesticide use cannot therefore be rejected as a reason for the declines and local extinctions of the kestrel and cuckoo-shrike.     

泰国Khao Yai国家公园豹猫的道路生态学

为了解道路对豹猫（Prionailurus bengalensis）空间生态和时间生态的影响,使用无线电追踪技术对6只雌性个体和4只雄性个体进行了为期1—18个月的监测。道路上的车辆主要在白天出现,似乎不影响豹猫的位置或活动,即便在周末或假期车辆增加时,情形也是如此。需要更多的研究来确定本文报道的结果是否代表了该物种的整体情况,或者仅仅特定于KaoYai国家公园。需要该物种更多的自然性方面的数据为野生动物管理者决策提供根据.     

泰国Khao Yai国家公园豹猫和云豹的生态和保护

于1997年10月到1999年10月在泰国KhaoYai国家公园对两种同域分布的物种（即豹猫和云豹）进行了研究。使用带诱饵的陷阱捕捉了这些动物,进行麻醉,确定了性别、年龄,并戴上了无线电项圈,对6只雌性豹猫和4只雄性豹猫进行了1—18个月的无线电追踪。豹猫在干旱季节的利用区域大于雨季,雄性利用的区域大于雌性。在夜间和晨昏时节,豹猫活动增加,但是并没有节律性活动。所有豹猫个体在旱季和雨季的活动都相似,但雄性个体的白天活动多于雌性。豹猫的行走距离有性别差异但是没有季节差异;其食物以鼠类为主。分别对1只雌性云豹和1只雄性云豹进行了17个月和7个月的无线电追踪,雌性个体的活动面积为39．4km^2,而雄性个体活动面积为42．2km^2,核心区都是2．9km2。云豹对半绿林的使用大于其它类型的植被,在晨昏和夜间的活动增加,其活动无节律。     

Enclosure utilization and activity of Round Island geckos (Phelsuma guentheri)

This study evaluated space use and activity of individually housed Phelsuma guentheri to formulate recommendations for environmental enrichment. Gecko location within small (0.03 m³) and large (0.22 m³) vivaria and substrate use data were collected over five 24 h periods. Thermogradients within each enclosure type were determined by measuring temperature at various heights. From these data, geckos' space use, activity cycle, and substrate preference were calculated in relation to temperature changes and photoperiod. Geckos did not utilize their environment uniformly. Heavily utilized locations contained cage furnishings or hides. Geckos avoided the use of vertical glass walls. Thermogradients were not actively utilized; however, when given the opportunity, geckos would orient towards natural sunlight. Enclosure size did not affect activity cycle, which was nocturnal with crepuscular peaks. Recommendations for enclosure improvement include provision of more furnishings and hides at different thermal levels. An alternate focal heat source other than UV light is recommended to provide warmth without light. Larger enclosures may encourage more uniform use of available space. Transparent glass may not be an appropriate substrate for these geckos. Once recommendations have been implemented, a similar study must be conducted to assess benefit. © 1995 Wiley-Liss, Inc.