Model life tables for the larger old world monkeys

Mortality statistics for 25 populations of the larger Old World monkeys (members of the subfamily Cercopithecinae) were evaluated with a competing hazard model of mortality. The best eight of these life tables were combined to generate a standard model life table representative of the mortality patterns of these primates. Two applications of the standard model to smooth, graduate, and compare life tables based on limited and defective data are presented.     

Actuarial senescence in laboratory and field populations of Lepidoptera

1. Recent observations of actuarial senescence – an increase in mortality rate with age – have challenged the assertion that the brevity of adult insect life spans precludes ageing. 2. Here the rate of senescence in 22 species of Lepidoptera was quantified by fitting demographic models to adult survivorship data drawn from a range of field and laboratory studies. 3. Senescence was evident in all 22 species investigated, with a model of age‐related mortality consistently fitting the survivorship curves significantly better than an alternative model which assumes constant mortality. 4. The rates of senescence varied significantly among species. The rates of senescence also differed significantly between sexes for all species tested, but not in a consistent way.     

Optimizing return‐on‐effort for coral nursery and outplanting practices to aid restoration of the Great Barrier Reef

Coral nursery and outplanting practices have grown in popularity worldwide for targeted restoration of degraded “high value” reef sites, and recovery of threatened taxa. Success of these practices is commonly gauged from coral propagule growth and survival, which fundamentally determines the return‐on‐effort (RRE) critical to the cost‐effectiveness and viability of restoration programs. In many cases, RRE has been optimized from past successes and failures, which therefore presents a major challenge for locations such as the Great Barrier Reef (GBR) where no local history of restoration exists to guide best practice. In establishing the first multi‐taxa coral nursery on the GBR (Opal Reef, February 2018), we constructed a novel scoring criterion from concurrent measurements of growth and survivorship to guide our relative RRE, including nursery propagule numbers (stock density). We initially retrieved RRE scores from a database of global restoration efforts to date (n = 246; 52 studies) to evaluate whether and how success commonly varied among coral taxa. We then retrieved RRE scores for Opal Reef using initial growth and survivorship data for six key coral taxa, to demonstrate that RRE scores were high for all taxa predominantly via high survivorship over winter. Repeated RRE scoring in summer is therefore needed to capture the full dynamic range of success where seasonal factors regulating growth versus survivorship differ. We discuss how RRE scoring can be easily adopted across restoration practices globally to standardize and benchmark success, but also as a tool to aid decision‐making in optimizing future propagation (and outplanting) efforts.     

Survivorship in Wild Frogs Infected with Chytridiomycosis

Chytridiomycosis is an emerging infectious disease that has been implicated as the causative agent of many recent amphibian population declines and extinctions that have taken place in relatively pristine locations worldwide. While there exists a growing body of literature regarding the effect of the fungus on experimentally infected frogs, few studies have examined the effect of the fungus on apparently healthy wild frogs from nondeclining, infected populations. We examined the temporal pattern of chytrid infection in individually marked Stony Creek Frogs (Litoria wilcoxii) at a lowland site in southeast Queensland, Australia. We provide the first evidence that wild frogs are capable of both acquiring chytridiomycosis as adults, and also of clearing their infections entirely. Changes in disease status in individual frogs largely tracked changing climatic conditions, with infections tending to appear in cooler months and disappearing in warmer months. Though 27.2% of the adult frogs we sampled were infected at some point in the study, we found no evidence that chytridiomycosis was negatively affecting adult survivorship, suggesting either: (1) chytrid-induced mortality in this population is generally restricted to metamorphs and juveniles; (2) this population was not exposed to conditions which favored lethal disease outbreaks; or (3) this population has evolved sufficient resistance to the disease to persist relatively unaffected.     

Reproductive life history of South African cheetahs (Acynonyx jubatus jubatus) at the San Diego Zoo Wild Animal Park, 1970–2005

We analyzed 35 years of data from a captive breeding program of cheetahs to determine basic reproductive life history characteristics of females. Breeding females ranged in age from 2.7–10.5 years. Sixteen females and over 13 males produced 129 cubs in 36 litters, with an average litter size of 3.6. Older females produced significantly fewer cubs per litter than younger females, but cub survivorship was comparable across female ages. Sex ratio was balanced at birth and 71% of infants survived the weaning period. Given that the reproductive output of captive cheetahs in our study is similar to that in other zoologic institutions and to cheetahs in the wild, we suggest that reproductive deficits in captive cheetahs arise from the inability of some pairs to breed, due to a lack of mating preference, rather than from a species‐wide problem. Zoo Biol 0:1–8, 2006. © 2006 Wiley‐Liss, Inc.     

土壤含水量对桔小实蝇蛹期存活的影响

浸水时间、土壤含水量对桔小实蝇Bactroceradorsalis(Hendel)蛹的存活及成虫羽化的影响的研究结果表明:(1)不同浸水时间对桔小实蝇蛹存活率的影响不同。浸水时间越长,蛹存活率越低;浸水对初期蛹的影响较大,蛹龄越大,浸水作用效果越低。浸水时间(TW)、蛹期(AP)和蛹存活率(SP)之间关系符合以下模型:SP=0.4165-0.00307TW+0.2290AP-0.00004496T2W-0.0002528A2P+0.00008258TWAP。(2)土壤含水量对桔小实蝇成虫羽化影响明显。当土壤含水量较低或较高时,羽化率都明显受到抑制。相对含水量在30%～80%之间,蛹的羽化率较高。相对含水量(Ws)和成虫羽化率(E)之间存在以下关系:E=0.396+0.01985W-0.000181W2。     

Combining archive territory mapping data and aerial photography to investigate bird–habitat relationships: a case study from the Lincolnshire coast

Capsule Habitat associations of breeding birds in a complex coastal environment are clear, interpretable and mostly consistent between years.

Aims To match archive territory mapping data with historical aerial photographs and develop data handling and analytical techniques for the study of bird–habitat relationships.

Methods Bird registrations were digitized from archive British Trust for Ornithology Common Birds Census maps and habitat characteristics from contemporaneous aerial photographs. The resulting maps were overlaid and ranks of habitat preference for 15 species calculated using compositional analysis. Similarity analysis identified species with consistent habitat profiles across years. Cluster analysis identified groups of species with similar patterns of habitat use.

Results A total of 5400 registrations of 15 species in 14 habitats were analysed. Of these, 13 species showed stable patterns of habitat association across survey years. Clear differences and similarities in habitat preferences among the species were identified. The results may be used to inform conservation and management programmes in this and similar environments.

Conclusions Extensive archives of bird survey data can be used to study bird–habitat relationships and to measure the effects of natural and anthropogenic environmental change if contemporaneous aerial photographs can be sourced.