bluuebunny/crossref_metadata_2025 huggingface dataset:
Gross anatomy of the gastrointestinal system of harp seals (Phoca groenlandica)
Authors: Olsen M. A. , Nilssen K. T. , Mathiesen S. D.
Published: May 2009

The gross anatomy of the gastrointestinal system of 12 harp seals (Phoca groenlandica) was investigated. Harp seals have a typical carnivore monogastric stomach. The tissue wet weight of the stomach of harp seals represented 27.01 (S.D. 3.99)% (n= 12) of the total gastrointestinal tract (GI‐tract). All animals were killed while resting on the ice, and had empty stomachs, but when expanded with water to a 30cm pressure the stomach contained 0.60 to 1.60 litres, representing 1.00 (S.D. 0.26)% (n= 12) of the body mass. The small intestine ranged in length from 20.44 to 25.32m, being 14.36 (S.D. 1.58) times the body length, and the tissue wet weight constituted 67.61 (S.D. 4.55)% of the total GI‐tract (n= 12). Both caecum and colon were short, maximally 5 and 78 cm, respectively, being 0.022 (S.D. 0.005) and 0.38 (S.D. 0.06) times the body length (n= 12). The caecum tissue wet weight was only 0.18 (S.D. 0.04)% of the total GI‐tract weight, while the colon tissue wet weight contributed to 5.33 (S.D. 1.19)% (n= 12). It is concluded that harp seals have relatively long intestines compared to minke whales eating a comparable diet in the North Atlantic Ocean.
Rhopalaea cloneyi (Ascidiacea, Cionidae), a new deep‐water ascidian from the coastal waters of British Columbia
Authors: Vaazquez E. , Young C. M.
Published: May 2009

A new species of solitary ascidian from the British Columbia fjords, Rhopalaea cloneyi is described. R. cloneyi is characterized by its strong musculature, consisting of 14‐15 longitudinal bands which are branched several times on the ventral side, converging to the endostylar band of the thorax. Its differences with the seven species of the genus Rhopalaea described up to the present are discussed. A checklist of the associated benthos found with the nine deep ascidians from this area observed with the PISCES IV submersible shows that R. cloneyi and Bathypera feminalba are found associated with the brachiopods Crania and Laqueus, the asteroid Mediaster aequalis and the anthozoid Stomphia.
Life history, secondary production and microdistribution of Stenopsyche angustata (Trichoptera: Stenopsychidae) in a tropical forest stream
Authors: Dudgeon David
Published: May 2009

The ecology of the net‐spinning caddisfly Stenopsyche angustata (Stenopsychidae) was investigated in Tai Po Kau Forest Stream (TPKFS), New Territories, Hong Kong, over a two‐year period (1977‐79). Quantitative benthic samples were taken from different microhabitats in the stream on 45 occasions and, in combination with light‐trap catches of adult caddisflies (taken during 1983‐84 and 1985), were used as a basis for investigating the life‐history pattern and estimating secondary production of this species. Annual production over the period 1977‐79 was 940.4 mg AFDW 0.5m−2, and was slightly higher in 1977‐78 (1004.1 mg AFDW 0.5 m−2) than in 1978‐79 (926.1 mg AFDW 0.5 m−2). This variation reflected slight inter‐year differences in mean population densities and biomass of S. angustata, which ranged from 41.1 individuals 0.5 m−2 and 113.3 mg AFDW 0.5 m−2 in 1977‐78 to 38.6 individuals 0.5 m−2 and 105.9 mg AFDW 0.5 m−2 in 1978‐79. Mean values of these parameters over the two‐year study period were 39.8 individuals 0.5 m−2 and 109.4 mg AFDW 0.5 m−2. Stenopsyche angustata appeared to be bivoltine in TPKFS, but growth was rather asynchronous with some adult emergence and continuous recruitment throughout the year. Production: biomass ratios were almost constant (varying between 8.74 and 8.87) over the two years of the study.

Mean densities of Stenopsyche angustata varied significantly across TPKFS. Larvac were most abundant in midstream microsities, and least numerous close to the stream banks. Population densities in intermediate microsites were significantly less than in midstream, but significantly greater than at bankside microsites. Stepwise multiple regression analysis and multivariate statistics (principal components analysis followed by regression) were used to investigate the relationship between larval densities in each benthic sample and the sediment characteristics, detrital standing stocks, and algal biomass in the microenvironment where the sample was taken. Regression analysis revealed that S. angustata microdistribution was influenced by sediment grain‐size characteristics (kurtosis of the grain‐size distribution), and algal biomass (specifically, the amounts of chlorophyll b), and the relationship between algal biomass and larval densities was negative. Multivariate statistics followed by regression analysis confirmed the interactive effects of both biotic and abiotic influences upon S. angustata abundance. Approximately 20% of the variance in abundance in TPKFS was attributable to sediment characteristics and algae, but it seems plausible also that current speed had a direct effect on the microdistribution and abundance of S. angustata through an influence on the rate of supply of food to the filter‐feeding larvae.
Millipede communities in rehabilitating coastal dune forests in northern KwaZulu/Natal, South Africa
Authors: Van Aarde R. J. , Ferreira S. M. , Kritzinger J. J.
Published: May 2009

The rehabilitation, after mining, of coastal sand dunes north of Richards Bay by Richards Bay Minerals began some 18 years ago, and resulted in the simultaneous availability of a known‐aged series of stands representative of coastal dune forest succession.

A survey of the millipede community in this area revealed increases in species diversity and a decrease in their density, with an increase in stand age. Development of these communities is characterized by replacement and addition of species, typical of ecological succession. Colonization of areas disturbed by mining reflects on the species reservoir present in the surrounding unmined forests with apparent pioneer species being either replaced or complemented by the relatively slow invasion of secondary species.

Comparisons of age‐specific millipede community variables on rehabilitating dunes with those recorded in relatively undisturbed dunes suggest that the development of communities results from autogenic succession initiated through habitat rehabilitation. With several community parameters in rehabilitating dune forests being similar to those recorded in undisturbed forests, it is concluded that the millipede community can be restored through management options based on principles relating to ecological succession.
Halichondrids or axinellids? Some problematic genera of sponges with descriptions of new species from the Strait of Gibraltar (southern Iberian Peninsula)
Authors: Carballo J. L. , Uriz M. J. , Garcia‐Gomez J. C.
Published: May 2009

The axinellids and the halichondrids are two of the most conflictive sponge groups from a taxonomic point of view, owing to the simplicity of the morphological characters that would allow discrimination between taxa at a supraspecific level. In this sense, some of the species dealt with in this study provide an example of the controversy that exists when a species must be assigned to one of these groups. The species Axinyssa digitata is redescribed. We also propose to move the species Dictyonella madeirensis to the genus Scopalina, and the validity of the recent family Dictyonellidae Soest, Diaz & Pomponi (1990) is supported. Moreover, two new species are described: Dictyonella alonsoi, characterized by thick monactine megascleres which undergo different tip modifications, and Ciocalapata almae, characterized by the presence of anisostrongyloxeas in two size categories together with oxeas.
Migration of Walruses (Odobenus rosmarus) in the Svalbard and Franz Josef Land area
Authors: Wiig Ø. , Gjertz I. , Griffiths D.
Published: May 2009

Thirty‐four walruses (Odobenus rosmarus) were fitted with satellite transmitters (PTTs) from 1990 to 1993 in order to study the distribution of the population in the Svalbard area. Twenty‐eight were caught at Svalbard and six at Franz Josef Land. All were males except one female caught at Franz Josef Land. At Svalbard, one walrus was caught on the west coast of Spitsbergen, while the others were caught at southern Edgeøya. All walruses were caught in the period from mid‐July to early September. The PTTs provided information on location for periods ranging from 0 to 212 days. The results of the satellite trackings show that there is a migration of male walruses between most of the walrus areas at Svalbard and Franz Josef Land. In particular, it seems that migration of males from southern Edgeøya to Kvitøya, Viktoria Island, and Franz Josef Land is common. The walruses winter in the southern parts of Svalbard, as well as within the winter pack‐ice of north‐eastern Svalbard, which contains numerous open leads. The only walrus at Franz Josef Land that was followed to mid‐winter stayed in the area and therefore supports the view that walruses also winter in that area. It is assumed that the majority of walruses at Svalbard are males from one common Svalbard‐Franz Josef Land stock. The walrus in the Svalbard‐Franz Josef Land area today belong to a recovering population. Their current distribution and behaviour may therefore differ from that found in Svalbard in former times.
Effects of bot fly (Alouattamyia baeri) parasitism on a free‐ranging howler monkey (Alouatta palliata) population in Panama
Authors: Milton Katharine
Published: May 2009

To evaluate effects of persistent bot fly (Alouattamyia baeri) parasitism on a host population of Panamanian howler monkeys (Alouatta palliata), a 68‐month study was carried out which included: (i) examination of the parasite's life cycle; (ii) monthly estimates of prevalence and mean intensity; (iii) monitoring of howler mortality; (iv) censuses of howler monkey troops; and (v) analysis of blood samples from infected and uninfected monkeys. A complete life cycle of A. baeri takes approximately 13 weeks; larvae remain in howlers for approximately six weeks, passing through three instars. Overall prevalence of infection was 60%, overall mean intensity 2.8±0.04. No difference in prevalence or mean intensity was found between adult males and females. As a class, juveniles had a significantly higher prevalence and a significantly lower mean intensity than adults; the adult and juvenile classes both showed a significantly higher prevalence and mean intensity than the infant class. Such differences may relate to characteristics of younger age classes rather than host selectivity on the part of the parasite. Although larvae were observed in the howler population throughout the year, relative density fluctuated from month to month, showing from one to three significant peaks per year. Larvae were most abundant during the mid‐to‐late rainy season (Aug.‐Nov.). Relative density was strongly correlated with howler mortality. Several hematological parameters including serum albumin levels and albumin/globulin ratio were significantly lower in individuals with heavy larval burdens. No endoparasites or diseases were found in blood samples. I conclude that the annual pattern of howler mortality results from a synergistic effect between the age, physical condition, and fat reserves of parasitized individuals, the size of the larval burden, and increasing dietary stress as the rainy season progresses. The lack of growth in this closed primate population over >20 years apparently results, in large part, from primary and secondary effects of bot fly parasitism.
Predation by grass snakes (Natrix natrix) at a site in southern England
Authors: Reading C. J. , Davies J. L.
Published: May 2009

The prey and feeding frequency in free‐living grass snakes was studied during 1993 and 1994 at a site in southern England. Individual snakes and common toads were recognized using PIT tags and a small number of adult snakes were radio‐tracked over long periods to determine predation rates.

Grass snakes fed, almost exclusively, on common toads (adult, juvenile, and tadpoles). A positive correlation was found between prey size and snake size. Large snakes did not appear to prey upon small toads, although clearly capable of doing so.

Male and female snakes ate large meals (toads) approximately every 20 days between May and September, with females fasting for a period of about 45 days during gestation and egg‐laying. After allowing for differences in the number and size of toads predated by male and female snakes, the mean amount of food consumed per day was estimated to be 2.3% and 1.6% of body weight.
Genetic and seasonal variation in body colour of the Australian death, adder, Acanthophis antarcticus (Squamata: Elapidae)
Authors: Johnston Greg
Published: May 2009

Two colour morphs, red and grey, are recognized in the death adder, Acanthophis antarcticus, an Australian elapid snake. The inheritance of these morphs appears to be controlled by two alleles at a single autosomal locus, with red dominant to grey. Both morphs show seasonal changes in dorsal reflectance. They show similar reflectance patterns in winter, whereas in summer red animals become less reflectant, grey animals become more reflectant. Populations in northern and eastern Australian contain predominantly red snakes, whereas southern populations consist of mostly grey snakes. Selection for crypsis through substrata colour matchng may be important in maintaining the polymorephism.
Life history of the vaquita, Phocoena sinus (Phocoenidae, Cetacea)
Authors: Hohn A. A. , Read A. J. , Fernandez S. , Vidal O. , Findley L. T.
Published: May 2009

The vaquita, Phocoena sinus, is the most endangered marine cetacean primarily due to incidental mortality in fishing nets. We examined a sample of 56 vaquitas to study the life history of this poorly known species. The age structure was bimodal, with 62% of the specimens from 0‐2 years and 31% from 11‐16 years; the sample contained no specimens from ages 3‐6 years. The oldest individual was estimated to be 21 years old. All specimens less than three years old were sexually immature and all greater than six years old were mature. The asymptotic length of females (140.6 cm) was significantly greater than that of males (134.9 cm), although no difference was detected in asymptotic girth or body mass. Reproduction is synchronous; births occurred from late February to early April and maximum testes activity occurred from mid‐March through to at least mid‐April. Our observations from this small sample suggest that the calving interval is greater than one year. The sample was too small for many quantitative analyses, although it appears that lifespan, patterns of growth, age at sexual maturation, seasonal reproduction, and large testis size are similar to the harbour porpoise, P. phocoena, in a highly exploited and well‐studied population from the Bay of Fundy. A significant difference, however, is that harbour porpoise females give birth annually, indicating that the rate of increase in the vaquita population is likely to be lower than that in the harbour porpoise. Without immediate cessation of fishing pressure, this fragile population will collapse, resulting in extinction of the vaquita.
The respiratory system of Halarachne halichoeri (Halarachnidae: Gamasida: Anactinotrichida)
Authors: Pugh P. J. A.
Published: May 2009

Halarachne halichoeri Allman (Halarachnidae: Anactinotrichida), a parasitic mite occuring in the nasal cavities of the grey seal, Halichoerus grypus, has an unusual apneustic respiratory system, which is described in detail. The main functions of this system are to facilitate gaseous (tracheal) respiration and prevent foreign material being forced into the tracheae under increased pressure experience when the host seal dives. Possible responses of the system to the rapidly changing pressure regimes are described.
Interspecific agonistic behaviour in small mammals in a Mexican high‐elevational grassland
Authors: Fa J. E. , Sanchez‐Cordero V. , Mendez A.
Published: May 2009

Field trials were conducted throughout an annual cycle to study the role of agonistic behaviour in explaining the relative abundance of the volcano mouse (Neotomodon alstoni) in a small mammal community in high‐altitude grasslands of central Mexico. Intrasexual contests between N. alstoni and three other sympatric rodents (Peromyscus melanotis, Microtus mexicanus, and Reithrodontomys megalotis) were performed. Male and female P. melanotis (100 and 67% of contests, respectively) and M. mexicanus (82 and 100%) were aggressively dominant over N. alstoni, whereas R. megalotis (80 and 100%) were not aggressive. Agonistic behaviour in this species did not explain its greater abundance in the community.
Suckling behaviour in the brown long‐eared bat (Plecotus auritus)
Authors: McLean and J. A. , Speakman J. F.
Published: May 2009

Thirty‐two adult female brown long‐eard bats were taken into captivity. Eight individuals gave birth to single young in captivity (known mother‐young pairs), 10 were lactating when captured (putative mother‐young pairs), and the remaining 14 bats were non‐reproductive. Bats were maintained in five groups consisting of females from sigle(n=3) or mixed (n=2) wild roosts. All bats were housed in outdoor, free‐flight enclosures and fed mainly on free‐flying noctuid moths. Bats were individually were determined daily (n=152) for a single gruup of bats containing four known mother‐young pairs and five non‐reproductive bats. The probability of a being attached to the nipple declined from 100% of records at 1‐5 days of age to 5% of records at 36‐40 days of age. Females were always found suckling their own young. Suckling associations were determined using infra‐red sensitive video‐recordings of bat behaviour within the roost box. For both known (n=8) and putative mother‐young pairs (n=10), there were no records of young attached to lactating females other than their own mothers (from the same or different wild roosts).
The relation between male body size, fighting, and mating success in Dawson's burrowing bee, Amegilla dawsoni (Apidae, Apinae, Anthophorini)
Authors: Alcock John
Published: May 2009

Males of the bee Amegilla dawsoni (Anthophorini) vary greatly in size, with some of the largest individuals as large as the largest females, a rare phenomenon in insects. The occurrence of unusually large males appears to be the product of sexual selection for fighting ability. As predicted from this hypothesis: (1) males regularly competed aggressively to be in the best position to mount sexually receptive, virgin females as they emerged from the ground; (2) larger males usually won fights for potential mates, as demonstrated by the fact that males able to defend sites with an emerging female were larger on average than males they kept at bay; (3) the fighting advantage of large males translated into greater mating success. Males captured while mounted on a female were significantly larger on average than randomly captured matesearching males in two of three populations sampled in 1993. Moreover, males known to mate more than once were consistently larger than single‐mating males in the 10 samples taken from four populations examined in 1994. Thus, a large male mating advantage applies across years and among populations, making it potentially advantageous for females of Dawson's burrowing bees to produce large, superior fighting sons about the same size as their daughters.
Ecological factors influencing sexual segregation and group size in fallow deer (Dama dama)
Authors: Thirgood S. J.
Published: May 2009

Grouping patterns in fallow deer Dama dama were studied between 1986‐9 by direct observation from transects of eight populations in the New Forest and adjacent agricultural land in southern England. Study populations were chosen on the bais of pronounced differences in population density, sex ratio, and dispersion, and differences between the sites in habitat availability and patterns of habitat use.

Within both forest and agricultural study sites, a large majority of female deer was observed in single sex female groups throughout the year. The lowest levels of female segregation occurred during the autumn reproductive period. Males generally exhibited lower levels of sexual segregation than females, particularly during winter and spring. In the forest sites, winter and spring mixed‐sex groups in agricultural sites contained mature males throughout the year and were not exclusively based on habitats used for feeding. There was a negative correlation between the extent of winter and spring male segregation and population sex ratio, suggesting that males join female groups when male densities are relatively low.

Female group size varied seasonally in all sites, attaining maximum values in winter or spring and minimum values in summer or autumn. This was not a reflection of changing patterns of habitat use; group size varied seasonally in both open and closed habitats. Female groups were larger in open habitats than in closed habitats throughout the year. The size of female groups varied between the study sites but there were no clear differences in overall female group size between the forest and agricultural sites. There was a tendency for open habitat group size to be largest in the forest sites and closed habitat group size to be largest in the agricultural sites.

Female group size overall was unrelated to the proportion of each site occupied by closed habitat. However, an increase in the amount of closed habitat was reflected by a decrease in closed habitat group size. Female group size overall was negatively related to the use of closed habitat; not surprisingly, an increase in use of open habitats resulted in increased overall group size. Female group size overall was not related to density; large groups occurred in both high and low density sites. However, in high density populations, open habitat group size was larger and closed habitat group size smaller than in low density populations.
Snake relationships revealed by slow‐evolving proteins: a preliminary survey
Authors: Dowling H. G. , Hass C. A. , Hedges S. Blair , Highton R.
Published: May 2009

We present an initial evaluation of relationships among a diverse sample of 215 species of snakes (8% of the world snake fauna) representing nine of the 16 commonly‐recognized families. Allelic variation at four slow‐evolving. protein‐coding loci, detected by starch‐gel electrophoresis, was found to be informative for estimating relationships among these species at several levels. The numerous alleles detected at these loci [Arp‐2 (42 alleles). Ltlh‐2 (43), Mdh‐1 (29), Pgm (Z)] provided unexpected clarity in partitioning these taxa. Most congeneric species and several closely‐related genera have the same allele at all four loci or differ at only a single locus. At thc other extreme are those species with three or four unique alleles; these taxa cannot be placed in this analysis. Species sharing two or three distinctive alleles are those most clearly separated into clades. Typhlopids, pythonids, viperids, and elapids were resolved into individual clades. whereas bods were separated into boincs and erycines, and colubrids appeared as scveral distinct clades (colubrines, natricines, psammophines, homalopsines, and xenodontines). Viperids were recognized as a major division containing three separate clades: Asian and American crotalines. Pabearctic and Oriental viperines, and Ethiopian causines. The typhlopids were found to be the basal clade, with the North American erycine boid Chrrrino and the West Indian woodsnakes Tropidophi, Y near the base. A number of species and some small clades were not allocated because of uninformative (common, unique, or conflicting) alleles. Of the 21 S species examined, five to eight appear to have been misplaced in the analysis of these electrophoretic data.
Temporal variation in reproductive allocation in a shield bug Elasmostethus interstinctus
Authors: Mappes Johanna , Kaitala Arja , Rinne Veikko
Published: May 2009

We investigated changes in the reproductive output and the effect of female phenotype on reproductive parameters in a shield bug Elasmostethus interstinctus (L.) (Heteroptera: Acanthosomatidae) over the whole reproductive period. At the beginning and the middle of the reproductive period eggs were smaller than at the end of the period. Clutch mass and number of eggs per clutch decreased in laying sequence, first clutches being much larger than any of the later ones. Lifetime fecundity correlated positively with female size: large females produced more eggs and lived longer than small ones. Egg size did not vary with female size. Offspring survival until adulthood increased with egg weight. Individuals overwinter before reproduction, and because the nymphs from later‐laid eggs have the least time to gather resources before overwintering, it may be important for later‐laid eggs to be of high quality. Reproductive allocation varies during the reproductive period; females allocate resources relatively more to offspring number at the beginning of the reproductive period and more to offspring quality at the end of their life.
The sexual strategy of the central long‐toed salamander, Ambystoma macrodactylum columbianum, in south‐eastern Washington
Authors: Verell Paul , Palton Janet
Published: May 2009

The sexual strategies of salamanders are largely‘unobservable’owing to the low visibility typical of their preferred breeding habitats. We conducted both field and laboratory studies to investigate the sexual strategy of the North American central long‐toed salamander, Ambystoma macrodactylum columbianum. Capture‐recapture and cohort‐marking of salamanders at an aquatic breeding site indicated that males arrive before females and remain in the water for longer periods of time (measured in weeks, rather than days as for females). We estimate that the overall duration of the breeding season is short, three weeks or less. Courtship between single males and females is characterized by repeated bouts of axillary amplexus, separated by multiple episodes of spermatophore deposition. Amplectant males provide females with considerable tactile stimulation in the form of head‐rubbing. Unpaired males attempt to displace amplectant males from their partners by wrestling with them. In addition, unpaired males appear to interfere in ongoing courtship encounters during the spermatophore deposition stage, perhaps attempting to 'steal’inseminations. We suggest that explosive scramble‐competition polygyny best describes the mating system of A. m. columbianum. Operational sex ratios are probably male‐biased throughout the short breeding season, leading to intense competition among males for mates. Mate choice (by either sex) probably is of little importance as a determinant of mating success.
Dispersal and extra‐territorial prospecting by slender‐tailed meerkats (Suricata suricatta) in the south‐western Kalahari
Authors: Doolan S. P. , Macdonald D. W.
Published: May 2009

Dispersal in slender‐tailed meerkats or suricates, Suricata suricatta, in the south‐western Kalahari occurred mainly during the early breeding season, and was age‐ and sex‐dependent. Among yearlings, more males than females were immigrants, but more females than males disappeared. There were no sex differences in dispersal among two‐year‐olds, but among animals aged three years or older, more males than females emigrated. Most dispersers moved into adjacent bands or joined other transients, and females apparently suffered higher rates of mortality than males. Kinship with the same‐sex or opposite‐sex breeder had no discernible effect on the likelihood of dispersing. Both males and females made prospecting forays to other groups, apparently to assess dispersal and breeding opportunities. Males made frequent and repeated forays, often in coalitions with other band members or transients, whereas prospecting by females was generally solitary, and they were not known to make multiple forays. Prospecting males successfully took over dominance of two bands, and attempted to take over bands on three other occasions. Animals attempting to join or follow a band (trailers) behaved submissively and were readily chased by residents, whereas those attempting a dominance takeover (invaders) scent‐marked at a high rate and showed no submissive behaviours. Dispersing meerkats maximized reproductive success by increasing their mating opportunities, while animals which delayed dispersal received indirect benefits by helping to raise kin.
Reproductive behaviour in Chironomus anthracinus (Diptera: Chironomidae), with a consideration of the evolution of swarming
Authors: Tokeshi M. , Reinhardt K.
Published: May 2009

Reproductive behaviour in Chironomus anthracinus Zetterstedt (Diptera: Chironomidae), one of the most ubiquitous species in cold‐temperate lakes of Northern Europe, was investigated in Lough Neagh, Northern Ireland. Aerial swarming is an indispensable part of mating in this species. It has been recognized that adults, emerging from offshore, travel to inshore resting sites for physical/sexual maturation, before gathering at lake margins to form swarms. After copulation, females immediately travel back to open‐water sites (up to 1000m offshore—the longest oviposition flight recorded for a chironomid species) for oviposition. Protandry was evident and sex ratios were completely reversed in the near‐shore swarming site and the offshore oviposition site. A sequence of mating behaviour was clarified, involving an initial grasp, landing, an end‐to‐end position, and separation. There was a high incidence of homosexual (male‐male) grasps, indicating that grasping is initiated with a fairly crude cue, and many (heterosexual) grasps failed to proceed to a correct mating position. This resulted in an estimation of only one out of eight grasps resulting in a proper copulation. More egg masses were found in the surface water farther offshore, together with spent females. An egg mass contained c. 1000 eggs and hatching occurred within one month of oviposition.

Sexual differences in the pattern of reproductive migration between the emergence/oviposition site offshore, the inland resting site, and the near‐shore swarming site, and the modes of mating and mating success achieved, together point to a possibility that the conspicuous swarming behaviour in this species may have evolved primarily through mate selection on the part of females. A swarm occurring at the end of the males’ lives serves as an efficient mechanism for females to select the best‐quality mate, while males have no other strategy than to participate vigorously in a swarm if they are to attain a reproductive success with choosy females. Thus, two sexes apparently adopt different strategies in their reproductive life: males spend their energy in swarming, while females pass through the swarm site with a quick but guaranteed reward and spend their remaining energy in reaching offshore sites with muddy substrata which provide the best chance of survival for the offspring.
Establishing body‐size indicators in a study of female spruce grouse Dendragapus canadensis
Authors: Reynolds S. J.
Published: May 2009

Seven measurements were taken from 72 adult and yearling spruce grouse Dendragapus canadensis hens collected over a 10‐year period from north‐eastern Ontario, Canada. A principal components analysis (PCA) indicated keel ridge length, keel total length, and femur length, these being the most representative measurements of general body size. Skeletal mass, caecal length, wing length, and foot length had lower character loadings on the first principal component axis (PC1), suggesting they are unreliable measurements of body size. Measurements taken from bones (i.e. keel, femur) were more representative of general body size than external morphometric measurements (e.g. wing and foot length) which ornithologists traditionally use to estimate body size. Pre‐laying adults were the smallest individuals and pre‐laying yearlings the largest in the population studied. A discriminant functions analysis (DFA) of the seven measurements, with separated body mass as an eighth variable, demonstrated distinct separation between pre‐laying and post‐laying groups of birds on the basis of separated body mass. Keel ridge length was further implicated as an effective variable in the discrimination of birds from different laying groups.
Locomotor patterns, territory, and tunnel utilization in the mole‐rat Spalax ehrenbergi
Authors: Zuri I. , Terkel J.
Published: May 2009

The mole‐rat (Spalax ehrenbergi) is a solitary, subterranean rodent that excavates and inhabits its own tunnel system. The present study employed continuous radio‐telemetry in order to determine the structure and use of the mole‐rat's territory throughout the year. The use of radiotagged animals revealed that the spatial division of individuals in one area cannot be predicted simply on the basis of the above‐ground distribution of mounds. It was shown that mole‐rat territories undergo constant change in use and location throughout the year, with tunnel lengths averaging 18.7 ± 4.0 m in the dry season and 39.1 ± 7.1 m in the rainy season. The basic pattern of the mole‐rat tunnel system consisted of a main tunnel, 20–40 cm below the ground, with several short secondary tunnels branching off it. Most of the nests were connected to the tunnel system by two or more exits. During one 24‐h period, a mole‐rat travelled about 17 times the total length of its territory. Mole‐rats are active for about 50% of the time all year round, mainly during the day, and always return to the same nest for resting periods. The mole‐rat traverses its territory by walking short distances (c. 2 m) interspersed with pauses at certain permanent sites. While the pattern of territorial patrol normally remains uniform, under threat the patrol ceases to be homogeneous and the frequency of visits to confrontational areas increases. At these locations, the mole‐rat produces its‘head drumming’(vibrational) communication in order to announce its presence and defend its territory.
Effect of food availability on nestling growth and fledging success in manipulated pallid swift broods
Authors: Cucco M. , Malacarne G.
Published: May 2009

Growth rate and fledging success were assessed in natural and manipulated broods of the pallid swift Apus pallidus. Daily measurements of chick mass, wing length, and insect abundance allowed us to examine the short‐term variation of chick growth in relation to food availability.

The number of fledged nestlings increased with brood size. Wing length and body mass were slightly but significantly smaller in larger broods, and the nestlings of enlarged broods needed longer to fledge. We discuss how these differences could influence survival after fledging.

Hatching asynchrony caused a significant difference in growth among siblings, and the difference between the oldest and youngest chick was greater in larger broods.

Chick growth was independent of daily food availability. We suggest that this was due to an increased effort of the parents at their expense, when food availability was poor.

The ability of this species to raise an additional chick is in line with most findings on birds, but partially in contrast with results for the common swift in which, at least during poor seasons, the additional nestling caused an increased mortality and lowered the reproductive success.
Sperm storage secretion of female cellar spiders (Pholcus phalangioides; Araneae): a gel‐electrophoretic analysis
Authors: Uhl Gabriele
Published: May 2009

Glandular secretion in the genital cavity of female Pholcus phalangioides was removed and investigated gel‐electrophoretically. Different staining techniques indicate that the secretion contains proteinaceous substances. Some protein fragments show a clear reaction to glyco‐ and lipoprotein staining procedures.

After copulation, female P. phalangioides keep the spermatozoa embedded in the secretion in the genital cavity. Since the spermatozoa are immobile, i.e. coiled and encapsulated, until shortly before oviposition, a nutritive function of the secretion during sperm storage is unlikely. The viscous quality of the material probably serves to retain the sperm mass in the sperm storage site. Lipoproteinaceous components are assumed to prevent desiccation of the sperm mass. Retaining the spermatozoa and maintaining them in a favourable environment are the most plausible functions of the secretion of female P. phalangioides. In spider species which possess receptacula seminis other functions can be attributed to sperm storage secretions.
Adoption in African wild dogs, Lycaon pictus
Authors: McNutt J. Weldon
Published: May 2009

Parental care of unrelated young is occasionally misdirected and maladaptive from an individual fitness perspective (e.g. interspecific brood parasitism). Alternatively, adults may‘adopt’dependent young and gain direct benefits irrespective of the degree of relatedness. For social species whose fitness is partially a function of group size, direct benefits of increasing group size may provide a mechanism favouring adoption independently of the inclusive fitness consequences. African wild dogs. Lycaon pictus, are social carnivores for which group size has been positively crrelated with reproductive success and competitive ability. Co‐operative breeding by wild dogs has been described previously as strongly kin‐selected and helpers were assumed to be invariably closely related to offspring. However, observations from this study show that the assumption that helpers are related to those they help is not always valid. A minimum of 25% of study area packs (n=12) contained nonbreeding adults that provided parental care for unrelated pups. Costs of adopting unrelated weaned wild dog pups are slight or nonexistent except for delayed costs due to later potential conflict with mature same‐sex adoptees over access to mates. Immediate and delayed direct benefits identified here are associated with increasing group size and may indicate important mechanisms underlyig adoption and the evolution of helping behaviour in wild dogs.
Social behaviour of captive bush dogs (Speothos venaticus)
Authors: Macdonald D. W.
Published: May 2009

The bush dog, Speothos venaticus, is a rare forest‐dwelling South American canid. Social behaviour of a captive pack of three adult males and three adult females was observed over four years in a large enclosure. The dogs appeared to be compulsively sociable, sleeping in close physical contact, travelling together in single file, and feeding communally with minimal aggression. An alpha pair was dominant, but there was no clear hierarchy within the pack as a whole. There were, however, separate male and female hierarchies. The pack engaged in various communal behaviours, including greeting ceremonies in which individuals mutually submitted to one another. All dogs urine marked frequently, both sexes adopting postures to direct urine upwards and to soak their fur in odour. Only the alpha female bred successfully, and all other group members carried and guarded the young. These observations are discussed in the contexts of canid social behaviour and the breeding in captivity of this endangered species.
Diet and biology of the laughing owl Sceloglaux albifacies (Aves: Strigidae) on Takaka Hill, Nelson, New Zealand
Authors: Holdaway R. N. , Worthy T. H.
Published: May 2009

The faunal composition of two Holocene fossil deposits of small vertebrates provided new information on the diet and biology of Sceloglaux albifacies, a strigid owl endemic to New Zealand. The taxonomic composition and several measures of diversity of the prey accumulation are given. Most taxa in the deposit had a mass of 50‐150g, but species up to 400g were also present. The owl was a generalist feeder, but the prey biomass distribution showed that a few taxa provided most of its energy requirements. Changes in the diet appeared to coincide with the appearance of Rattus exulans, the Polynesian rat, and the consequent decline or extinction of several prey. The ecologies of extant taxa represented in the deposit suggest that the owl was primarily a nocturnal forest species. Many prey taxa were terrestrial. Species richness was higher for both diurnal (by 50%) and nocturnal (by 63%) vertebrates in the deposit than in the present fauna around the site. Analysis of possible guilds in the pre‐human and present faunas of Takaka Hill suggests that ground‐frequenting taxa were most severely affected by extinctions; three guilds vanished entirely.
Infectious diseases as main causes of mortality to beavers Castor fiber after translocation to the Netherlands
Authors: Nolet B. A. , Broekhuizen S. , Dorrestein G. M. , Rienks K. M.
Published: May 2009

Between 1988 and 1994, 58 beavers were translocated from the Elbe region (Germany) to the Netherlands. In 43 animals, radio‐transmitters were implanted with a pulse interval which was dependent on body temperature; subsequently, 22 of the released animals were found dead and the cause of death was investigated. Infectious diseases were the most important cause of death (50%), in particular yersiniosis and leptospirosis. Yersiniosis is relatively rare in the source population along the Elbe, and leptospirosis has not been reported before in beavers. We hypothesize that the immune system of the translocated animals was weakened by stress at a time of exposure to new pathogens. In future translocations of beavers, we recommend to reduce the stress, improve the hygiene, and to vaccinate against Yersinia pseudotuberculosis and leptospirosis prior to the release.
Predator‐prey interactions among some intertidal gastropods on the Great Barrier Reef
Authors: Castell L. L. , Sweatman H. P. A.
Published: May 2009

On an intertidal reef flat at Orpheus Island on the Great Barrier Reef, the gastropods Turbo brunneus and juvenile Trochus niloticus share the same habitat with the predatory gastropod Thais tuberosa. To determine if the two prey species differed in their antipredator behaviour and interactions with the predator, we examined: (1) the distributional pattern of the three species in the field; (2) the proportion of mortality attributable to non‐crushing predators (i.e. Thais tuberosa) in T. brunneus and T. niloticus, determined by the frequency of freshly dead and undamaged shells; and (3) the response of T. brunneus and T. niloticus to T. tuberosa in laboratory and field experiments. We compared the responses of hatchery‐reared and wild juvenile T. niloticus to determine if lack of previous exposure to the predator affected the behaviour of cultured juveniles. Finally, (4) we studied prey choice by Thais tuberosa.

We found that: (1) the field distribution of all three species showed high overlap and prey and predator were often found in close proximity; (2) the proportion of recently‐killed, undamaged shells was 28% for T. brunneus and 10% for T. niloticus; (3) T. brunneus and T. niloticus responded very differently to the predator: Turbo brunneus showed a conventional flight escape response, moving nine times faster than normal when close to T. tuberosa. The flight response was observed in all trials with T. brunneus in the laboratory, but only in 52% of trials in the field. In contrast, T. niloticus did not change speed but instead released a white mucus in the presence of the predator. Response in the field was also less intense than in the laboratory. Cultured and wild T. niloticus showed the same response when exposed to T. tuberosa. although cultured juveniles were, on average, slightly more active than wild juveniles. Lastly, (4) Thais tuberosa showed a strong preference for T. brunneus as prey. Food value, expressed as dry flesh weight, did not explain this preference. Capture rate of the preferred species T. brunneus fell to zero in water containing mucus released by T. niloticus.

The results indicate that predation by T. tuberosa is more intense for T. brunneus than for T. niloticus and that a likely cause for this difference lies in the antipredator responses of the two prey species. The mucous response of T. niloticus appeared to be more effective for avoiding predation by T. tuberosa than was the flight response of T. brunneus.
Haematological changes by splenic respiratory compensation in the cave salamander, Hydromantes genei
Authors: Frangioni G. , Brizzi R. , Borgioli G.
Published: May 2009

Like other amphibians, the salamander Hydromantes genei, an exclusively terrestrial lungless plethodontid which lives in cold humid caves, possesses a haematological mechanism of respiratory compensation: the spleen can hoard erythrocytes, which are then released into the bloodstream when necessary, analogous to what happens in the Italian crested newt (which, however, is predominantly aquatic). The cave salamander, anaesthetized with chlorobutanol and kept in a humidity‐saturated environment at a constant temperature long enough for its haematological conditions to stabilize, presents homogeneous and very low blood parameters at the extreme temperature ranges to which it is adapted (6 °C and 18 °C): about 16 109 red blood cells/1, haematocrit value approximately 12, and haemoglobin concentration slightly below 3g/dl. The increase in temperature triggers the release of erythrocytes into the bloodstream from the spleen, which shrinks from 0.8% of the animal's body weight at 6 °C to 0.25% at 18 °C; however, a parallel increase in blood plasma maintains the blood composition unaltered. At 24 °C, a critical temperature for this species, the erythrocyte parameters increase by 50% owing to plasma loss, as happens in other amphibians in hypoxic conditions.
Recrudescence of sexual activity in a reproductively quiescent colony of the Damaraland mole‐rat (Cryptomys damarensis), by the introduction of an unfamiliar and genetically unrelated male—a case of incest avoidance in‘queenless’colonies
Authors: Rickard C. A. , Bennett N. C.
Published: May 2009

Colonies of the eusocial Damaraland mole‐rat, Cryptomys damarensis, are founded from a single reproductive pair of animals genetically unrelated by common descent. All non‐reproductive members of the colony are progeny of this reproductive pair. In colonies where the reproductive female has been experimentally removed or has died a natural death, there is a strict incest avoidance and the colony remains reproductively quiescent. Reinstatement of sexual activity in a queenless colony may be brought about in the laboratory by the introduction of an unfamiliar and unrelated adult male.

In the queenless colony under study, there was a marked change in social structure with an increase in Landau's index of linearity from 0.8 to 0.9 on introduction of the new male. The unrelated male became a high ranking dominant reproductive male. The youngest, but most dominant n on‐reproductive female became sexually active and subsequently became pregnant and hence acquired the position of reproductive female. The new reproductive female exhibited heightened progesterone (9nmols/mmol creatinine) and oestradiol (3000pmols/mmol creatinine) concentrations in the urine relative to the other non‐reproductive females. These hormone concentrations were indicative of a reproductively active female.

Behavioural and hormonal data are presented to show that sexual activity can be re‐instated in queenless colonies of laboratory maintained mole‐rats by the introduction of unrelated male mole‐rats.