bluuebunny/crossref_metadata_2025 huggingface dataset:
Observations on the morphology and taxonomy of two Parachordodes species (Nematomorpha, Gordioida, Chordodidae) in southern New England (USA)
Authors: Smith Douglas G.
Published: March 2009

Two nematomorph species are recorded from New England and described: Parachordodes lineatus, a little‐known North American species, and P. violaceus, a European species not previously verified for North America. The identity and species status of P. lineatus is firmly established and the presence of P. violaceus in North America is confirmed. Description is based both on light microscopy, which is found to be sufficient to distinguish the two species of Parachordodes, and scanning electron microscopy, which is necessary to elucidate details of cuticle structure and male posterior morphology. The status of the genus Gordionus in North America and the practice of splitting genera within the Gordioida are discussed.
Patch use and prey defence in a mammalian myrmecophage, the echidna (Tachyglossus aculeatus) (Monotremata: Tachyglossidae): a test of foraging efficiency in captive and free‐ranging animals
Authors: Abensperg‐Traun M. , Dickman C. R. , Boer E. S. De
Published: March 2009

Echidnas (Tachyglossus aculeatus) in wheatbelt reserves in Western Australia are primarily termite‐ and ant‐eaters. Using captive and free‐ranging animals, we tested whether echidnas respond to high density patches of these prey and also to differences in their mechanisms of defence. When feeding on termites, free‐ranging echidnas generally adjusted their foraging effort in response to prey abundance, increasing their rate of energy intake by digging deeper and allocating more time to patches where prey were abundant. Such efficient foraging occurred irrespective of whether termite defence was mandibulate, chemical, or a combination of both, as in Amitermes neogermanus. Echidnas invested little effort in species of Drepanotermes in the field despite their abundance at local food patches, probably because the soldiers are large and aggressive and produce copious quantities of pungent defence secretions. Echidnas also avoided Nasutitermes exitiosus in the field but ingested other species with chemical defence such as Tumulitermes. Captive echidnas decreased their foraging effort on N. exitiosus only when soldiers were abundant (400 per unit area) and the soldier to worker ratio was high (80:20), hence avoidance of this species by free‐ranging echidnas may reflect the species'ability to mobilize quickly large numbers of soldiers to colony breaches. When feeding on ants in the field, foraging effort and prey energy in food patches were not correlated, possibly because ants responded rapidly to colony breaches by emerging to meet the predator. More extensive soil excavations by foraging echidnas to capture ants were thus unnecessary, minimizing foraging effort. Captive and free‐ranging echidnas rejected ants 7 mm (except in the presence of energy‐rich eggs), and > 10 mm long, respectively, reducing foraging efficiency to zero when encountering such prey. With such exceptions, the results suggest that echidnas make efficient use of patchily distributed prey and generally adjust their foraging efforts to match actual energetic returns.
Behavioural reactions of desert bighorn sheep to avian scavengers
Authors: Stockwell CraigA.
Published: March 2009

I report previously undocumented encounters between avian scavengers and desert bighorn sheep (Ovis canadensis nelsoni). These encounters are of interest because they occurred only during the nursery season when lamb mortality was high. Desert bighorn sheep responded to the presence of avian scavengers with typical anti‐predator behaviours, which may indicate that avian scavengers are potential predatorsorthat desert bighorn sheep are unable to distinguish between avian scavengers and avian predators.
Hybridization and gene flow in house mice introduced into an existing population on an island
Authors: Berry R. J. , Triggs G. S. , King P. , Nash H. R. , Noble L. R.
Published: March 2009

Seventy‐seven house mice (Mus domesticus) from the Orkney island of Eday were released on the Isle of May, Firth of Forth in April 1982. The May had a long‐established mouse population, which was effectively homozygous at 71 allozymic loci scored; the Eday population had a heterozygosity at allozymic loci of 5% (80 loci scored) and was homozygous for three pairs of Robertsonian fusions. Introduced alleles at six loci expressed in blood were scored in animals trapped on the May at the beginning and end of the breeding season each year from 1982 to 1988. Hybrids between native and introduced animals were found in all parts of the island six months after the original release. All the introduced alleles survived and increased in frequency, albeit to different extents. There was no clear evidence of natural selection from differential survival of individuals or seasonal fluctuation of allele frequencies, but the change and apparent stabilization of frequencies after about three years (at different levels to both the parental Eday population and in the animals released) implies that some controlling factors must have acted.

These results were wholly unexpected. House mouse populations are divided into small demes, apparently with very restricted gene flow between them. The introduced mice on the May may have been successful because the native population had a low variability, but the latter had persisted successfully for over a century and certainly had a normal social structure. The spread of the Eday alleles to stability in the May population destroys the myth that population division inevitably restricts gene flow in house mice, and draws attention to the importance of coadaptation (or ‘genetic architecture’) in maintaining variation and affecting allele frequencies.
Phase delay of the natural photoperiod alters reproductive timing in the marsupial Antechinus stuartii
Authors: McAllan B. M. , Joss J. M. P. , Firth B. T.
Published: March 2009

The dasyurid marsupial Antechinus stuartii (20–40 g) has a brief, highly synchronized mating period in spring followed by complete male mortality. Analysis of breeding times in nature suggests that the rate of change of photoperiod is the main Zeitgeber for reproductive timing in this species. To test this hypothesis the natural photoperiod was phase delayed by two months, one experiment beginning in late summer, and the other in the autumn, before the spring breeding period.

The reproductive cycle of males and females exposed to the delay in summer was synchronously delayed by two months, coincident with the exact duration of the delay. Animals exposed to the two month phase delay in autumn also exhibited a delay in reproductive timing, but it was less synchronized than either the control or the other experimental group. Reproduction in control animals exposed to natural photoperiod was synchronous with that of a wild population monitored simultaneously. It is therefore likely that the rate of change of photoperiod is the dominant Zeitgeber for the reproductive cycle in this species.
An ecological study of small rodents in the thicket‐clump savanna of Lengwe National Park, Malawi
Authors: Happold D. C. D. , Happold M.
Published: March 2009

A community of small rodents was studied in thicket‐clump and grassland savanna of Lengwe National Park, Malawi, from September 1984 to June 1985. Nine species were recorded on a 1·1 ha grid and five assessment lines, using a capture‐mark‐release technique. The three commonest species (and their percentage proportions) were Mastomys natalensis (47%), Acomys spinosissimus (24%) and Saccostomus campestris (11%). Population numbers on the grid fluctuated from–30 individuals/ha, and the numbers on the assessment lines fluctuated from–57 individuals. There were two peaks of population numbers during the year: the first was in the early wet season (when individuals emigrated from dry season refugia and there was limited reproduction) and the second was in the mid dry season (when young born at the end of the wet season entered the trappable population). The population was comprised mainly of subadults in the late dry season, adults and some young in the wet season, and young and subadults in the early and mid dry seasons. Population survival rates were low with only 30–50% of individuals surviving to the following month. The magnitude of population fluctuations are related to the strong seasonality of climate, flooding and grass characteristics; in this respect, the community of small mammals in Lengwe National Park shows similarities to those of the Kafue Valley in Zambia and the Chobe Valley in Botswana.
Hibernation in the mountain pygmy possum Burramys parvus (Marsupialia)
Authors: Geiser Fritz , Broome Linda S.
Published: March 2009

Mountain pygmy possums Burramys parvus (40 g) disappear from their Mt. Kosciusko boulder fields from May to October/November and it is assumed that they hibernate during this time. However, laboratory studies did not observe the characteristic hibernation pattern of placentals, which, throughout the hibernation season, show long bouts of torpor (several days to weeks) that are interrupted by short (< 1 day) normothermic periods. We investigated the pattern of hibernation in juvenile (N = 8) and adult (N = 8) male and female B. parvus in the laboratory at an air temperature that was similar to that in the field during winter. Adults commenced hibernation earlier and hibernated longer (about seven months) than juveniles (about five months). All adult individuals hibernated whereas only six of the eight juveniles did so. Hibernating animals showed distinct seasonal changes in the duration of torpor bouts. Torpor bouts were short (about five days) at the beginning, long (12–20 days) during the middle, and short again at the end of the hibernation season. Normothermic periods were usually shorter than one day. The pattern of the seasonal change of torpor bout duration differed between juveniles and adults and between sexes. Body temperature during mid‐hibernation was regulated at about 2 ° c in females and 3 ° C in males and the metabolic rate was similar to that of hibernating placentals.
Scaling of limb joint surface areas in anthropoid primates and other mammals
Authors: Godfrey Laurie , Sutherland M. , Boy D. , Gomberg N.
Published: March 2009

Recently it was reported that limb joint surface areas scale positively allometrically with body weight in anthropoid primates. This was attributed to the biomechanics of weight bearing: larger animals must require relatively larger joint surfaces to withstand relatively greater weight‐related stresses on the joints. Our data on humeral and femoral geometry and joint surface areas in 73 species belonging to six mammalian orders (including primates) demonstrate that positive allometry of joint surface areas is not a general phenomenon for mammals and cannot have its basis among Anthropoidea in the biomechanics of weight bearing. We argue that, to the extent that positive allometric scaling of joint surface areas occurs in anthropoid primates, it is an artifact of differences in positional behaviour among distinct taxonomic groups that also happen to differ widely in body weight. Furthermore, we argue that, among mammals ranging in body size from sportive lemurs to giant pandas, functionally similar groups tend to exhibit: (1) linear dimensions (especially diameters and shaft circumferences) that scale in direct proportion to each other; and (2) joint surface areas that scale in direct proportion to the squares of linear dimensions and to the 2/3 power of body mass. In other words, limb bones of functionally similar animals fit the theoretical model of geometric similarity (or skeletal isometry). Differences in relative sizes of joint surface areas are related to differences in force transmission and movement potential among functionally distinct groups of animals.
A simulation of evasive mimicry in the wild
Authors: Hancox A. P. , Allen J. A.
Published: March 2009

The hypothesis of evasive mimicry proposes that: (a) the conspicuous coloration of some animals has evolved to warn predators that they are good at avoiding capture; and (b) this conspicuous coloration is mimicked by other, less evasive species which thus gain protection from predation. We have tested these ideas with wild birds as the predators and red and yellow pastry ‘baits’ as the prey. We used a specially constructed bird table to make one of the colours good at ‘escaping’: when a bird was about to eat a bait the observer pulled a cord which activated a mechanism that made the baits of one colour (but not the other) drop out of the bird's reach. We first measured the overall selection by the naive birds by presenting, for one day, a ‘control’ of equal numbers of non‐evasive red and non‐evasive yellow baits. The birds were then trained for 20 days on equal numbers of evasive yellow and non‐evasive red baits, and were then again given a second control (in which the yellows were now non‐evasive ‘mimics’). The training was repeated for 18 days but with red as the evasive colour, and a third control was then presented (with reds now as the mimics). The proportions attacked daily in the two training sessions suggested that the birds were learning to ignore yellows in the first and reds in the second. In comparison with the first control, fewer yellows were eaten after they had been trained to ignore escaping yellows, and more were eaten after they had been trained on escaping reds. We conclude that the results are further evidence for the hypothesis of evasive mimicry.
The effect of seasonal food restriction on activity, metabolism and torpor in the South African hedgehog (Atelerix frontalis)
Authors: Gillies A. C. , Ellison G. T. H. , Skinner J. D.
Published: March 2009

Twelve South African hedgehogs (Atelerix frontalis) were subjected to nine‐week experimental protocol comprising four weeks of simulated summer conditions (14L: 10D and 25 °C), and transition week followed by four weeks of simulated winter conditions (10L: 14D and 15 °C).

Six control hedgehogs, with access to food ad libitum throughout the experiment, did not increase their energy intake during winter yet retained stable body mass. Six experimental hedgehogs, of similar body size, experienced restricted diet during the last three weeks of each season. These hedgehogs displayed significantly lower energy intake than controls during food restriction and lost approximately 7% of their body weight in both seasons, although this weight loss was not significant.

Both groups displayed lower digestive efficiencies in winter, together with decline in activity. However, there remained no significant effect of food restriction on these parameters.

Neither control nor experimental hedgehogs displayed torpor during summer and, whilst both groups became torpid in winter, the duration of torpor was significantly longer in experimental hedgehogs following food restriction.

Analysis of fluctuations in body mass suggest that experimental hedgehogs supplemented their restricted diet with energy derived from body reserves during both seasons. However, the ability of this species to modify the duration of torpor in response to additional energetic stress indicates that A. frontalis can control its energetic expenditure in order to limit the depletion of body reserves.
Do the Bivalvia demonstrate environment‐specific sexual strategies? A Hong Kong model
Authors: Morton Brian
Published: March 2009

The expression of sexuality, overall sex ratio and variation in sex ratio with age of 14 southern Chinese freshwater, brackish and marine bivalves have been investigated.

Freshwater species are often hermaphroditic and brooding, e.g. Musculium and Pisidium (Pisidiidae), while Corbicula fluminea (Corbiculidae) demonstrates wide intraspecific variability in sexual expression, but also broods. Anodontu woodiunu (Unionidae) and Limnoperna fortunei (Mytilidae) are dioecious, with low incidence of hermaphrodites in the former, but both have strong female‐biased overall sex ratio which does not change with age. Juvenile age classes of Corbicula cf. fluminalis have female‐biased sex ratio. A pronounced female bias is means to optimize reproductive success, by maximizing resource allocation into more energy‐demanding oogenesis, in temporally and spatially heterogeneous lacustrine habitats. In such habitats, moreover, there are probably diminishing returns to producing sons.

Mangrove and brackish water species are all dioecious (except Succostrea cuculluta) with slight male‐biased sex ratio overall, but are strongly male‐biased as juveniles. This strategy similarly optimizes success in fluctuating intertidal environment, where high rates of juvenile mortality may be expected possibly, for example, through enhanced predation. In such case, therefore, the greater investment in sons is prerequisite to an overall balanced sex ratio. The marine intertidal species, Perna ciridis (Mytilidae) and Donax semigranosus (Donacidae) have stable I:I sex ratio, notvvarying with age, and are representative of the ‘typical’ dioecious condition recorded for most marine bivalves.

Thus, although intraspecific variations in life history tactics and sexual strategies equip all species for variable environment, it is postulated that permutations of the ‘dioecious’ condition, mediated through variations in the sex ratio either overall or with age, broadly equip the Bivalvia for the total range of aquatic habitats.
Average daily metabolic rate of gerbils of two species: Gerbillus pyramidum and Gerbillus allenbyi
Authors: Degen A. Allan , Kam Michael
Published: March 2009

Gerbillus pyramidum and G. allenbyi are primarily granivorous, nocturnal rodents that are sympatric over many sandy areas of the Negev Desert. However, in their overall distribution, G. pyramidum occurs in extreme desert areas whereas G. allenbyi does not. We measured the average daily metabolic rate (ADMR) of gerbils of each species when they were offered pelleted diet. Given the difference in their distribution, we reasoned that the more xeric G. pyramidum would have lower ADMR than G. allenbyi; however, given the similarity in their diets, we reasoned that their ADMRs would be similar. The latter alternative was supported. ADMR of G. pyramidum (body mass = 31·9 ± 5·4 g) was 427·1 kJ·kg−0.75·d−1, 58% of that predicted for a rodent of its body mass; whereas ADMR of G. allenbyi (body mass = 22·3±2·3 g) was 387·7 kJ·kg−0.75·d−1, 49%) of that predicted. On the basis of these results, we suggest that factors other than their ADMRs are important in determining their geographical distribution.
Taxonomic status of the Farasan Island gazelle
Authors: Thouless C. R. , Bassri K. Al
Published: March 2009

The taxonomy of Arabian gazelles has been confused by single specimen collected from the Farasan Islands in the Red Sea in the 1820s. There is still population of gazelles on the islands. They form distinct taxon most closely related to the mountain gazelle Gazella gaiella, which is characterized by small size, grey‐brown colouring, very short horns in the female and rounded upper tooth‐row in the male. This gazelle bears no resemblance to the type specimen of G. arabica, said to come from the Farasan Islands. In this paper the Farasan gazelle is described as Gazella gazella Jarasani n. ssp.
The effects of changes in food availability on the breeding ecology of great skuas Catharacta skua in Shetland
Authors: Hamer K. C. , Furness R. W. , Caldow R. W. G.
Published: March 2009

Great skuas on Foula, Shetland have responded to a decline in the availability of sandeels since the late 1970s by increasing the proportion of other items in their diets. This change is correlated with the annual recruitment of sandeels in Shetland waters. Since 1983 there has been a 10‐fold increase in predation by great skuas upon other seabirds, as Furness & Hislop (1981) suggested might occur in response to a low availability of sandeels. Changes in diet have been accompanied by a 50% reduction in adult territorial attendance as adults increased their foraging effort, such that between 1987 and 1989 breeding adults were probably working as hard as they were able to. Despite this, breeding success was less than 40% in 1987 and less than 15% in 1988 and 1989. The major cause of breeding failure was predation of unguarded chicks by adults from neighbouring territories. The willingness of adults to expose their chicks to high predation risk is probably maintained because of a positive correlation between chick pre‐fledging growth and post‐fledging survival, which is expressed up to the age of two years and which will place a strong pressure upon adults to feed their chicks as well as possible. The high expenditure of effort by adults in 1987 and 1988 did not affect the weights of those birds incubating eggs in 1988 and 1989, but there was a slight (3%) decrease in egg size between the late 1970s and the late 1980s. Changes in the age structure of the breeding population and the absence in 1989 of 28% of adults colour‐ringed during incubation in 1988 suggest an increase in the rate of egress since the 1970s. These changes probably represent an increase in the long‐term costs of reproduction to adults at this colony.
Male—male aggression in the plethodontid salamander Desmognathus ochrophaeus
Authors: Verrell Paul , Donovan Adriana
Published: March 2009

Aggressive encounters between pairs of male mountain dusky salamanders (Desmognathus ochrophaeus) were staged in the laboratory in the absence of any obvious limited resource. We observed aggressive interactions which sometimes escalated to biting. Physical injuries were inflicted during some aggressive encounters; however, the consequences of injury for future fitness are uncertain. Several behaviour patterns used in contests apparently functioned as threat displays, and these sometimes ended contests before they escalated to biting. We could detect no significant influences of three types of asymmetries among males in determining the winners and losers of contests (body size, recent mating experience and familiarity with the testing arena). Three cases of ‘homosexual’ courtship were observed. Both intermale aggression and intermale courtship may be interpreted as forms of competition for mates.
Mass transfer efficiency between harp seal (Phoca groenlandica) mothers and their pups during lactation
Authors: Kovacs K. M. , Lavigne D. M. , Innes S.
Published: March 2009

We investigated the efficiency of mass transfer in lactating harp seals through serial measurements on individual mother‐pup pairs during the whelping seasons of 1988 and 1989. We also compared the influence of longitudinal versus cross‐sectional sampling on estimates of the efficiency of mass transfer. Among longitudinally sampled pairs, pups grew at an average rate of 2·3 ± 0·5 (mean ± S.D.) kg/d (N = 20). The concomitant mass loss by females averaged 3·1 ± 0·8 kg/d (N = 19). The mean efficiency of mass transfer was 77·0 ± 13·6% (N= 19 pairs).

Estimates of pup growth and female mass loss from regressions of cross‐sectional data were 2·0 kg/d and 3·1 kg/d, respectively. These values produce an estimate of 65% for the efficiency of mass transfer.

Consistent with the high efficiency of mass transfer, harp seal females contribute less of their total body mass to nursing (c. 28%) than most other phocids examined. The resulting energy savings may be important for females of an ice‐breeding species, which migrate a long distance shortly after weaning their pups
Analysis of the diet of Natterer's bat Myotis nattereri and the common long‐eared bat Plecotus auritus in the West of Ireland
Authors: Shiel C. B. , McAney C. M. , Fairley J. S.
Published: March 2009

The diets of Natterer's bat Myotis nattereri and the common long‐eared bat Plecotus auritus were investigated at a nursery colony of each species by analysis of droppings collected monthly from May to September. Respectively, 68% and 42% of the diets comprised items presumed to have been gleaned from foliage or other surfaces: diurnal insects, insects which rarely fly, and non‐flying arthropods. Such surfaces included the ground: centipedes were eaten by both bats, and the muscid, Scatophaga stercoraria, usually associated with cattle dung, was a common prey. Indeed, the prevalence of cattle‐farming around both of the bat roosts almost certainly contributed indirectly, in the form of S. stercoraria, to a significant part of the Diptera consumed. The chief food of M. nattereri was the larger Diptera, but Trichoptera, Hymenoptera and Arachnida were also important. Lepidoptera, Coleoptera and Hemiptera were minor prey, with Dermaptera and Chilopoda taken occasionally. Diptera, closely followed by Lepidoptera, together accounted for nearly two‐thirds of the diet of P. auritus. Also taken, in descending order of importance, were Trichoptera, Arachnida, Chilopoda, Coleoptera, Dermaptera, Hymenoptera and Hemiptera. Plecotus auritus, but not M. nattereri, was evidently able to take a few small insects such as aphids and lesser nematoceran Diptera.
Environmental factors influencing the use of habitat in the red fox, Vulpes vulpes
Authors: Cavallini P. , Lovari S.
Published: March 2009

The seasonal variation in habitat selection and its determinants were assessed weekly for a sample of three dog‐foxes and two vixens in an ecotonal area of the Tuscan coast, in Italy. The most utilized habitats were the maquis (scrubwood), meadows and pinewood. In the cold season the maquis was preferred to any other habitat, but in the warm months foxes made extensive use of meadows. On the other hand, no clear seasonal pattern of use was detectable for the pinewood. Food habits showed a seasonal variation: juniper berries were the staple food, forming by far the greatest part of the diet during the whole study, except in late spring through midsummer, when beetles and grasshoppers predominated. Availability indices for each main food category were calculated on a weekly basis. Distribution of juniper berries was found to be clumped, whereas insects were dispersed. It was also assessed that the former occurred almost entirely in the pinewood, while the latter inhabited mainly meadows and, to a lesser extent. the pinewood. Measures of fox activity in the three habitats were also taken. The fox diet correlated well to the seasonal abundance of the important food resources, which in turn was significantly correlated to meteorologic factors (temperature, number of rainy days). Surprisingly, the seasonal activity in the pinewood was inversely correlated to local food availability, i.e. juniper berries. This can be explained by the clumpedness of this food resource which, when abundant, allows foxes to become quickly satiated and to retreat to other, more preferred habitat such as the maquis. Such results caution against assuming that extensive time spent in a habitat is an indication of proportional feeding dependence on it.
Wing kinematics during natural leaping in the mantids Mantis religiosa and Iris oratoria
Authors: Brackenbury John
Published: March 2009

High‐speed flash photography was used to analyse wing movements of Mantis religiosa and Iris oratoria at the moment of take‐off during natural leaping. Wing kinematics are compared with those of the similarly designed locust wing. Iris oratoria showed strong coupling between leg extensor and wing depressor muscle activity immediately prior to take‐off, with a possible enhancement of jump momentum. A ‘clap and peel’ was observed in the hind wings of both species during the first downstroke. Supination in the mantid forewing is accomplished by a backward rotation of the whole of the main wing plate about the claval furrow. Both fore‐ and hind wings show pronounced ventral flexure at the lower point of stroke reversal. Camber was developed in the hind wing during the upstroke as well as the downstroke. Possible roles of the claval furrow and transverse flexion in protecting the forewing base against torsional forces generated at stroke reversal are discussed.
Size, movements, distribution and gonadal stage of the western king prawn (Penaeus latisulcatus) in a temperate estuary and local marine waters
Authors: Potter I. C. , Manning R. J. G. , Loneragan N. R.
Published: March 2009

Penaeus latisulcatus were collected monthly over three years from the large Peel‐Harvey Estuary and nearby shallow and deeper marine waters in south‐western Australia. The relationships between catch rates obtained by seine net, and various environmental variables and sampling locations in the estuary, strongly indicate that salinity and distance from estuary mouth exert a marked influence over the distribution and abundance of prawns within the estuary. Since commercial catches of prawns in the Peel‐Harvey were very low during the 1970s, when the macroalga Cladophora montagneana coated much of the substratum of the estuary, the extent of the preferred sandy substratum of P. latisulcatus is also assumed to affect abundance. The modal carapace lengths (CL) of males and females caught by beam tide nets during their migration out of the estuary were sharply defined and in each year remained similar during the migratory period (typically February to July), when freshwater discharge, salinity and temperature were changing markedly. Although this provides strong evidence that the time when king prawns leave the estuary is at least partly related to factors associated with the attainment of a certain body size, it is also relevant that the decline in catch rate was greatest in the year when salinity fell most rapidly. Migration reached a maximum between March and May and in each month peaked just after the full moon. Comparisons between length‐frequency data for emigrating prawns and prawns caught commercially by trawling in marine waters indicate that, after leaving the estuary, many P. latisulcatus migrate a few kilometres northwards and remain there for a few months. The months when the incidence of mature ovaries is relatively high in the larger of the trawled female prawns (CL > 30 mm) is consistent with the time of immigration of new recruits (2‐3 mm CL) into the estuary (December‐April). Penaeus latisulcatus start migrating into the Peel‐Harvey Estuary later than into inshore marine waters (November or December vs. September) and subsequently emigrate from this alternative nursery area at a larger size (carapace length > 20 mm vs. < 18 mm CL).
Larvae of Maculinea rebeli, a large‐blue butterfly, and their Myrmica host ants: wild adoption and behaviour in ant‐nests
Authors: Elmes G. W. , Thomas J. A. , Wardlaw J. C.
Published: March 2009

The behavioural interactions between caterpillars of Maculinea rebeli Hir. and their Myrmica ant hosts were studied, both in the wild at the time of adoption, and inside captive nests of six Myrmica species.

In the wild, freshly moulted, final instar caterpillars left their food‐plants at a time of day that coincided with the peak foraging activity of Myrmica (18:00‐20:00 h). Once on the ground, caterpillars made no attempt to search for Myrmica but settled and waited for foraging ants to find them, which took up to 1.5 h. There was no adoption ritual: foragers of any Myrmica species picked up the caterpillars within 1–4 sec of discovery, and carried them directly to their nests.

Caterpillars grew from < 2 mg to 110 mg in laboratory ant‐nests. About 60 mg was gained in autumn but 40% of this was lost during the winter, while the temperature was < 14 °C. Although caterpillars survived best with their normal host, Myrmica schencki, they could also survive in the nests of other Myrmica species. The presence of queen ants had no effect upon survival. The behaviour of the caterpillars was described and illustrated: this included the production of secretions that were drunk by the ants, begging for food and direct feeding by ants. The preferred solid food was ant eggs.

The results are discussed in terms of the social biology of Myrmica ants. It is hypothesized that Maculinea rebeli caterpillars mimic the touch pheromones of ant worker‐larvae. This would explain the inability of ants to recognize caterpillars before touching them, their immediate adoption by any Myrmica species after discovery, host specificity inside wild ant‐nests, the absence of queen‐effect and the intimate attention of host workers.
Reproductive response of Tatera leucogaster (Rodentia) to supplemental food and 6‐methoxybenzoxazolinone in Zimbabwe
Authors: Neal B. R. , Alibhai S. K.
Published: March 2009

The effects of 6‐methoxybenzoxazolinone (6‐MBOA) and supplemental food on the reproductive activity of Tatera leucogaster were examined using a field experiment. The experiment was carried out during the dry season when no pregnancies were observed. Animals provided with 6‐MBOA‐treated millet seeds for 10 days were not significantly different from animals provided with sham‐treated seeds. Supplemental food appeared to have no effect on female reproductive activity, but increased the body mass of both sexes and also the mass of the testes and seminal vesicles. These results provide no evidence for an effect of 6‐MBOA on reproductive activity of this equatorial rodent, but supplemental food may promote the maturation and recrudescence of reproductive organs in males.
Population biology of the metacercariae of Centrocestus formosanus (Trematoda: Heterophyidae) on the gills of Aplocheilus panchax
Authors: Madhavi R. , Rukmini C.
Published: March 2009

The population biology of metacercariae of Centrocestus formosanus (Nishigori, 1924) on the gills of the larvivorous fish, Aplocheilus panchax (Hamilton) was investigated based on data from examination of monthly samples of fish collected from a stream at Visakhapatnam during the period December 1983 to April 1986. The seasonal dynamics, dispersion pattern and long‐term changes were studied. No seasonality in prevalence and density of infection with metacercariae was observed. The recruitment of metacercariae occurred throughout the year. An increase in density of infection with increase in size of the fish was noted. Possible reasons for the observed distribution are discussed. The frequency distribution of the metacercariae followed the negative binomial at different times of the year. The data indicated an increase in degree of overdispersion with increase in size offish except for a slight drop in the largest size class. Long‐term changes in the abundance of metacercariae are given and a decline in parasite population abundance is noted.
Quantitative observations on the pulmonary anatomy of the domestic Muscovy duck (Cairina moschata)
Authors: Vidyadaran M. K. , King A. S. , Kassim H.
Published: March 2009

The lungs of five female domestic Muscovy ducks, mean body weight 1.627 kg, total lung volume 48.07 cm3, were analysed by standard morphometric methods. Principal results obtained are: lung volume per unit body weight, 30.17 cm3/g; volume densities of exchange tissue relative to lung volume, 49.24%, blood capillaries relative to exchange tissue, 29.63%, tissue of the blood gas (tissue) barrier relative to exchange tissue, 5.88%; surface area of the blood‐gas (tissue) barrier per unit body weight, 30.04 cm2/g; ratios of the surface area of the blood‐gas (tissue) barrier per unit volume of the lung and per unit volume of exchange area, 979 cm2/cm3 and 200.06 mm2/mm3, respectively; harmonic and arithmetic mean thicknesses of the tissue barrier, 0.199 μm and 0.303 μm, respectively. The anatomical diffusing capacity of the tissue barrier for oxygen (DtO2) and the total pulmonary diffusing capacity (DLO2), 49.58 ml O2/min/mmHg/kg and 4.55 ml O2/min/mm Hg/kg, respectively. The lungs of the domestic Muscovy duck appear to be about as well adapted anatomically for gas exchange as the lungs of wild anatid species, and there is no clear evidence that domestication has been associated with any deterioration in the anatomical capacity for oxygen uptake. The weight‐specific anatomical diffusing capacity of the lung for oxygen (DLO2/W) was about 3.6 times greater than the weight‐specific physiological value, a factor which falls within the expected range.
A new genus of the mite subfamily Platyseiinae from Jamaica (Parasitiformes: Ascidae)
Authors: Evans Gwilym O. , Baker Anne S.
Published: March 2009

Cheiroseiulus reniformis
n.gen., n. sp., a platyseiine mite from water pools on epiphytes in Jamaica, is described. The species is characterized by having a markedly hypotrichous opisthonotal chaetotaxy. A key is given to the genera of the Platyseiinae.
Population studies on feral American mink Mustela vison in Ireland
Authors: Smal C. M.
Published: March 2009

Populations of feral American mink Mustela vison were investigated in several study areas in Ireland, principally by capture‐recapture techniques. The populations were found to be essentially self‐regulating, with stress, weight loss and mortality evident during the winter and spring. The highest mean density recorded, in terms of animals per unit length of river or lake shore, was 1.4 individuals km−1 with a peak density of 2.3 individuals km−1, but population densities were considerably lower in most areas. Trappability and population structure, in age, sex and residency classes, varied between habitats, but population turnover was high, leading to complete replacement of individuals in two populations monitored for two years. The availability of the preferred prey, crayfish Austropotamobius pallipes appeared to be a major factor determining population size and preferred breeding areas. Control methods are either unnecessary or are likely to fail in most situations, and may be counterproductive.
Structure of the reproductive system of the squid Thysanoteuthis rhombus (Cephalopoda: Oegopsida)
Authors: Nigmatullin Ch. M. , Arkhipkin A. I. , Sabirov R. M.
Published: March 2009

The structure of the reproductive systems of mature males and females of the nektonic, oceanic squid Thysanoteuthis rhombus are described. The main peculiarities of the female system are relatively low capacity oviducts, set in a tight spiral, and hypertrophically developed oviducal glands with a very large second section. The male reproductive system is characterized by a long, narrow Needham's sac containing 10–15 large spermatophores 80–100 mm in length. The mesentery supporting the gonad, and protruding into it dorsally, is a characteristic feature in both sexes. The hectocotylus structure differs markedly from that in other squids and resembles that of sepiids. The reproductive system of T. rhombus possesses primitive features (pattern of gonad attachment and hectocotylus) but mostly secondary characters (small oviducts, very large oviducal glands and ovary). The complex morpho‐ecological adaptations of T. rhombus are reflected in the distinctive features of the reproductive system.
Bioassay evidence for a sex attractant pheromone in the large carpenter bee, Xylocopa varipuncta (Anthophoridae: Hymenoptera)
Authors: Minckley R. L. , Buchmann S. L. , Wcislo W. T.
Published: March 2009

A field bioassay was conducted to test i˜hethercompoundsp roduced in the thoracic gland of male X. varipuncta are involved in long‐range mate attraction. Filter paper impregnated with the two most abundant compounds of the male gland was placed in sites comparable to those used by territorial males during the time of day when mating activity occurs. Females visited these filter paper ‘lures’ as often as they visited unmanipulated males in the study area. Males with the chemical mixture added to their territories did not receive more matings than males at territories where we had not added the chemical mixture. These findings and other studies, summarized herein, support the hypothesis that the male gland produces a pheromone which functions as a long‐range sex attractant.
Evaluation of a method for determining the length of sperm whales (Physeter catodon) from their vocalizations
Authors: Gordon Jonathan C. D.
Published: March 2009

The click vocalizations of sperm whales often contain several regularly‐spaced, discrete pulses of sound. Norris & Harvey (1972) hypothesized that these were caused as a single pulse of sound produced at the front of the whale's head bounced between reflective air sacs at either end of the spermaceti organ. Thus the interval between pulses will be twice the travel time for sound along the length of the spermaceti organ. It should therefore be possible to determine spermaceti organ length and thence total body length by measuring the interval between these pulses. Several workers have used an equation relating inter‐pulse interval (IPI) to body length to estimate sperm whale body lengths acoustically.

In this paper, aspects of this technique are examined in some detail. In particular, variability in IPIs and trends in IPI with time and depth are investigated. Most importantly, for the first time IPIs in the vocalizations of whales of known lengths have been measured.

Variability in IPIs in the clicks of a single whale is acceptably low though there is a tendency for low and high values to occur in runs. There is no clear trend for IPI to alter significantly with the whale's depth or with the time since leaving the surface.

IPIs are positively correlated with body length though not as predicted by the equations used by previous workers. Some likely errors in these equations are discussed. A new empirically derived relationship between IPI and body length has been calculated, though more data are desirable to obtain a more accurate and reliable equation.
Reproductive cycles of male and female tuatara (Sphenodon punctatus) on Stephens Island, New Zealand
Authors: Cree Alison , Cockrem J. F. , Guillette L. J.
Published: March 2009

Cycles in gonadal activity and plasma sex steroid concentrations were investigated in wild female and male tuatara on Stephens Island, New Zealand. Females nest once every four years on average. Vitellogenesis is spread over the first three years, and mating, ovulation and nesting occur in the fourth. Oviducal eggs are carried for6–8 months before nesting. Although the length of this ovarian cycle is unparalleled among oviparous reptiles, the associated cycles in plasma concentrations of sex steroids are similar to those in other reptiles. Mean plasma concentrations of oestradiol increase during vitellogenesis, peak at mating, fall rapidly before or around ovulation, are low during most of gravidity, and rise slightly during late gravidity‐nesting. Plasma concentrations of testosterone show a similarcycle. Mean plasma concentrations of progesterone are low during vitellogenesis and peak around ovulation. This periovulatory surge falls within1–2 months, and mean concentrations are low during the final 5–6 months of gravidity. Male tuatara show an annual, pre‐nuptial reproductive cycle. Mean plasma concentrations of testosterone are low during winter, rise during spring, peak during midsummer‐early autumn, when pre‐nuptial displays and mating occur, and fall in mid autumn. Limited histological data indicate that spermiogenesis occurs during midsummer‐early autumn, and also support a previous study suggesting that there may be no period of complete testicular and epididymal regression. In comparison with the pre‐nuptial cycles of other temperate‐zone reptiles, the cycle in male tuatara shows a more prolonged duration of testicular activity and of rising or elevated plasma testosterone concentrations. The prolonged reproductive cycles of male and female tuatara may be adaptations to a temperate environment with cool summers and cool, but not freezing, winters.
Biotelemetry monitoring of translocated Crocodylus niloticus in Lake Ngezi, Zimbabwe
Authors: Hocutt C. H. , Loveridge J. P. , Hutton J. M.
Published: March 2009

Radiotelemetry was used from June 1986 through February 1987 to observe the movements of four Nile crocodiles, Crocodylus niloticus Laurenti, introduced into a resident population at Lake Ngezi, Zimbabwe. The use of surgically‐implanted transmitters was the first application of this technique on wild Nile crocodiles. A subadult female (194 cm TL, 35 kg) and two males (256 cm, 81 kg; 348 cm, 260 kg) wandered throughout the area. A large female (297 cm, 149 kg) moved > 12 km from her point of release to Ngezi River and nested; she guarded the nest site through 21 January 1987 when she moved the hatchlings to a nearby creche. A juvenile crocodile (120 cm TL, 8 kg) captured in Lake Ngezi was also monitored from June 1986 to February 1987. It traversed some 15 km of the shoreline of Lake Ngezi and moved as much as 10 km overnight. Evidence is presented that the translocated crocodiles, excluding the nesting female, exhibited exploratory behaviour throughout the nine‐month observation period, and did not establish home ranges per se.
The foraging ecology of a termite‐and ant‐eating specialist, the echidna Tachyglossus aculeatus (Monotremata: Tachyglossidae)
Authors: Abensperg‐Traun M. , Boer E. S. De
Published: March 2009

This study investigates the effect of food distribution on the selection of foraging habitats, and the relationship between food availability, diet, ambient temperature, activity, use of shelter and energy budgets, in a termite‐and ant‐eating mammal, the echidna, Tachyglossus aculeatus. In two Nature Reserves in the wheatbelt of Western Australia, 10 adults and six juveniles were radio‐tracked for II months during 1988. Animals were weighed monthly and their fresh faeces collected for dietary analysis. Available termite and ant energy was measured simultaneously in habitats where the echidnas foraged: woodland, mallee**, shrubland and heath. Termite energy formed the principal food of echidnas, possibly because of their greater abundance. Highest ingestion rates of termite energy during the hottest time of year may reflect increased moisture requirements. Adult animals preferred woodland and mallee for foraging, possibly because termite and ant energy was highest there. Juveniles exhibited no obvious habitat preference. Echidnas were active year‐round, with foraging peaks during spring and autumn, and animals gained weight then. Despite termite energy being highest in winter, echidnas were in negative energy balance during this period, possibly because they make smaller foraging efforts and have higher thermoregulatory costs. Foraging was principally nocturnal in summer, and mixed nocturnal/diurnal in winter. No foraging was observed below 9° and above 32°C, with a preferred range of 16–20°C. Echidnas were not apparently food‐limited because: (a) both adult and juvenile animals maintained, or gained, body weight even when termite energy was low; (b) juveniles foraged anywhere, irrespective of habitat, but still gained weight; and (c) there was no evidence for hibernation by wheatbelt echidnas, unlike in other parts of Australia where echidnas routinely hibernate in winter, possibly in response to food shortage. However, echidnas did show signs of short‐term torpor. Echidnas were active throughout the year, possibly because food was unlimited, and because use of subterranean shelter reduced thermoregulatory costs. The results of this study suggest that food distribution and ambient temperature play an important role in influencing daily and seasonal foraging activity in wheatbelt echidnas.
Some Antarctic and sub‐Antarctic species of Celleporidae (Bryozoa, Cheilostomata)
Authors: Hayward P. J.
Published: March 2009

Sixteen species of cheilostome Bryozoa, within the family Celleporidae Busk, 1852, are reported from Antarctica and the sub‐Antarctic south‐west Atlantic. Nine new species are described in the genera Osthimosia Jullien, 1888, Celleporina Gray, 1848 and Turbicellepora Ryland, 1963. Spigaleos gen. nov. is introduced for Cellepora horneroides Waters, 1904.