Factors affecting the distribution of small mammals in an urban area

We investigated the distribution of a range of small mammal species in five urban habitats in north‐west Bristol: residential gardens, woodlands, allotment gardens, scrub and a cemetery. Wood mouse Apodemus sylvaticus abundance in residential gardens was negatively related to the abundance of cats and the distance to the nearest patch of natural or seminatural vegetation. These results suggest that urban small mammal populations may be limited by predation and habitat fragmentation, although the effects of the latter may be offset by the availability of good quality gardens.     

Effects of diet quality on performance and nutrient regulation in an omnivorous katydid

1. Omnivores by definition eat both plants and animals. However, little is known about how diet macronutrient content affects omnivore performance, or the extent to which they can regulate macronutrient intake. We assessed these questions using the salt marsh katydid, Conocephalus spartinae Fox (Tettigoniidae). 2. In our first experiment we used artificial diets with different protein–carbohydrate ratios to assess the effects of diet quality on survival, growth, and lipid accumulation. We found that diets with a high protein–carbohydrate ratio negatively affected Conocephalus survival. Among surviving individuals growth was not significantly different across the treatments, but lipid content decreased significantly as the protein–carbohydrate ratio of diets increased. 3. In a second experiment we explored the ability of Conocephalus to regulate their protein–carbohydrate intake. Results revealed that Conocephalus did not feed randomly when presented with two nutritionally complementary foods. A detailed analysis of their protein–carbohydrate intake revealed selection for a protein‐biased diet, but a lack of tight regulate of protein–carbohydrate intake. 4. We discuss how key macronutrients can limit omnivores, and how nutritional flexibility may enable omnivores to persist in nutritionally heterogeneous environments.     

Immunization of rabbits with faecal extract of Pediculus humanus, the human body louse: effects on louse development and reproduction

Abstract Immunization of rabbits with a faecal extract of the human body louse (Pediculus humanus) induced a high titre of specific IgG. The mean weight of Wood taken by females fed on the immunized rabbits was significantly lower (29%) than taken by females fed on the control rabbits. The mean number of eggs per female fed on the immunized rabbits was significantly lower than for females fed on the control rabbits. The hatchability of the eggs laid by lice fed on immunized rabbits (91%) was significantly lower than of those fed on control rabbits (94%). The rate of development of nymphs fed on control rabbits was significantly higher than those fed on the immunized rabbits. There was no difference in survival rates of lice fed on immunized and control rabbits.     

Characterization of microsatellite loci in Sacramento perch (Archoplites interruptus)

We characterized 23 polymorphic tetranucleotide microsatellite loci for Sacramento perch (Archoplites interruptus). This species is extirpated in its native range, the Sacramento–San Joaquin Delta (California, USA), and is therefore targeted for recovery. A concerted effort is currently underway to re‐establish self‐sustaining populations of Sacramento perch in its native range. These microsatellites will be used to analyse the population structure of the species and, in conjunction with life history and physiological data, develop a comprehensive recovery plan.     

Validation of a Field Technique and Characterization of Fecal Glucocorticoid Metabolite Analysis in Wild Chimpanzees (Pan troglodytes)

Monitoring adrenocortical activity in wild primate populations is critical, given the well‐documented relationship between stress, health, and reproduction. Although many primate studies have quantified fecal glucocorticoid metabolite (FGM) concentrations, it is imperative that researchers validate their method for each species. Here, we describe and validate a technique for field extraction and storage of FGMs in wild chimpanzees (Pan troglodytes). Our method circumvents many of the logistical challenges associated with field studies while yielding similar results to a commonly used laboratory method. We further validate that our method accurately reflects stress physiology using an adrenocorticotropic hormone challenge in a captive chimpanzee and an FGM peak at parturition in a wild subject. Finally, we quantify circadian patterns for FGMs for the first time in this species. Understanding these patterns may allow researchers to directly link specific events with the stress response. Am. J. Primatol. 75:57‐64, 2013. © 2012 Wiley Periodicals, Inc.     

HYBRID FITNESS SEEMS NOT TO BE AN EXPLANATION FOR THE PARTIAL REPRODUCTIVE ISOLATION BETWEEN ECOTYPES OF GALICIAN LITTORINA SAXATILIS

Partial reproductive isolation between closely related groupsof organisms is suggested to be of central importance duringspeciation. Galician populations of Littorina saxatilis arephenotypically differentiated into an upper-shore and a lower-shoremorph. These mate assortatively in the mid-shore zone of overlap,and genetic assessment shows an impeded gene flow between theparental morphs. The traditional explanation as to why assortativemating occurs is that reproductive isolation is reinforced dueto hybrid unfitness. Earlier studies have, however, not foundhybrids to be less viable. Likewise, growth and migratory behavioursare merely intermediate between those of the parental morphs.In the present study we compared male and female fertilitycomponents of the parental morphs and the hybrids to test hypothesesof decreased hybrid fertility. The results showed that hybridmales were as fertile as other males, and hybrid females didnot produce fewer embryos, nor aborted embryos at a higher rate,than the parental morphs. ^* To whom correspondence should be addressed. (Received 19 March 1999; accepted 7 July 1999)     

Role of Blood Platelets in Haematophagy

RED blood corpuscles (RBC) suspended in saline induce gorging in many haematophagous insects because of their high intrinsic concentration of adenine nucleotides (ANS)^1–6. ANS are bound firmly inside the intact RBC, which raises the question of how they gain egress to contact the chemoreceptor surfaces and induce feeding. It has been suggested that saliva or secretions of the chemoreceptor surfaces act as ANS releasing agents¹. ANS release by haemolysis is discounted by the fact that all RBC found in the gut immediately after feeding are intact. Further, stereoscan electron microscopy of tsetse fly gustatory sensilla does not suggest that they operate by piercing the erythrocytes^7,8. Thus we decided to test the possibility that the chemoreceptors involved in blood identification receive an ANS stimulus from a source associated with, but not within the RBC.