Captive-born mountain gazelles (Gazella gazella), including 28 radio-collared and 54 tagged animals, were freed in Hawtah Reserve, Saudi Arabia, during 1991–95. The size (as minimum-area convex polygons) and spatial distribution of their individual ranges were determined from daytime radiotracking and sightings. Some adult males were territorial and territorial fidelity was >94%. Territories were maintained year-round and were arranged linearly along the wadi floor. Initially, the size of territories decreased as their density increased, but after density stabilized, median territory area was 0.6 km2. The ranges of up to four released females were centred on each territory and female core areas were arranged in clusters along the wadi. Female ranges became smaller as the density of territories increased. After females had dispersed, their annual range averaged about 1 km2 during both 1993 and 1994 in wadis without domestic livestock and where, consequently, plant standing crop was high. Where camels foraged and plant standing crop was low, female ranges averaged 4.6 and 1.6 km2 during these two years. Some females shifted their core area, and their annual range was twice as large. The range area of non-territorial males averaged 6.7 km2 and extensively overlapped the ranges of other bachelors. Bachelor males occasionally passed through territories, but some wadi sections were used often by bachelors and seldom by females. The size and spatial distribution of gazelle ranges did not change seasonally, despite the temporal variation in rainfall. Runoff concentrated in wadis and the consistent food supply there allowed gazelles to occupy small ranges, even though annual rainfall was low (<150 mm).

The feeding habits of the neotropical river otter Lontra longicaudis were studied in a headwater stream of the Atlantic Forest, south-eastern Brazil, for 17 months. The otters fed mainly on fish (93% of the scats), but invertebrates were also frequent items in the diet (78.9% of the scats), as observed for the same species in lentic habitats and for other species of Lontra as well. It is suggested that the high proportion of invertebrates in the diet in comparison to Lutra is related to differences in the dentition of the two genera. The observed seasonal variation in the diet of L. longicaudis was probably a result of fluctuations in the abundance of a main prey item, a megalopteran larva (Corydalus sp.). Prey selection, regarded as differences between rates of predation and relative abundance of food items, was demonstrated for the two most important groups of otter prey: fish and crustaceans. Although they are able to capture mobile prey, otters seem to prefer feeding on prey showing lower escape ability – among fish they select armoured catfish, and among crustaceans they select crabs.

Intra- and interspecific variation are analysed for the post-natal skull of the lacertid lizards Gallotia galloti, Acanthodactylus erythrurus, Algyroides marchi, Lacerta monticola, Lacerta vivipara, Podarcis bocagei, Podarcis hispanica, Podarcis muralis, Psammodromus algirus and Psammodromus hispanicus. Individual variations identified include: the presence/absence, number and morphology of some structures, mainly in the lacrimal, sclerotic ossicles and maxilla; the number and location of foramina and the degree of ossification of some processes in chondrocranial bones. No differences have been found between the sexes with respect to presence and morphology of the bones but some species show sexual dimorphism in the size and robustness of the head and this may be reflected in the individual. The most substantial variations seen are ontogenetic: the appearance of new traits; development of articulations; differences between species in the timing of the stages of development of a given structure; changes in the relative position of some cranial elements; and the degree of calcification or ossification of processes. A total of 63 characters showing interspecific variations are identified. Some have not previously been described while others used in previous studies are redefined here on the basis of new morphological information obtained.

The egg and hatchling of Sepia officinalis L. is relatively large, compared with those of other cephalopods. We review the information on growth, chromatophores, behaviour, prey capture, colour and body patterns of this sepiid, for correlation with changes in morphology and development of its central nervous system. We compare the early life of S. officinalis with that of the common octopod, Octopus vulgaris, Cuvier 1797. Sepia officinalis is initially benthopelagic but subsequently is mostly benthic in habit. Octopus vulgaris enters the plankton immediately after hatching and spends several weeks there before it settles to a life spent mostly on the bottom.

White-lipped peccaries (Tayassu pecari) and collared peccaries (Tayassu tajacu) are common ungulates of Amazonia that are integral to the ecosystem and are important sources of meat for local people. Information on the reproduction and productivity of peccaries is essential for implementing management practices that conserve peccary populations over short and long time-scales. This paper examines the reproductive biology of white-lipped and collared peccaries in the northeastern Peruvian Amazon in and around the Tamshiyacu-Tahuayo Community Reserve. Skulls and reproductive tracts of white-lipped and collared peccary were examined from hunted samples collected by local people, as part of a participatory wildlife management programme. In this Amazonian site both white-lipped and collared peccaries were in follicular and luteal stages year round. Similarly, conceptions, births and pregnancies were aseasonal for both species. Of white-lipped peccary females, 32.4% were pregnant (n = 219 adult females examined) compared with 46% of collared peccary females (n = 89 adult females examined). Overall, gross productivity was 0.53 foetuses/adult female for white-lipped peccaries and 0.89 foetuses/adult female for collared peccaries. Gross fecundity (number of female young produced/number of adult females) was 0.26 for white-lipped peccaries and 0.37 for collared peccaries. The estimated parturition–conception interval was 250 days (192–331 at the 90% confidence interval) for white-lipped peccaries and 129 days (80–205 at the 90% confidence interval) for collared peccaries. This study shows that reproductive productivity of white-lipped peccary is lower than collared peccary in the northeastern Peruvian Amazon. This difference in reproductive productivity has implications for management strategies, and suggests that white-lipped peccaries are more susceptible to the effects of hunting than collared peccaries.

Tadpoles of different species of frogs and toads display different tendencies to aggregate. We investigated some of the costs and benefits of aggregating in three British species by examining their behavioural responses to the presence of conspecifics, and by monitoring the performance of tadpoles under different levels of social interaction with other individuals. The common toad (Bufo bufo), an aggregating species, displayed higher levels of activity than the natterjack toad (B. calamita) and common frog (Rana temporaria), two species that form aggregations less frequently. Moreover, out of the three species, only B. bufo increased activity in the presence of conspecifics. In all three species, increased interaction between individuals resulted in increased variation in size. However, average growth rate was affected only in B. bufo, which grew faster when raised in isolation and not interacting with other individuals. Under certain conditions intraspecific competition therefore seems to be more important than social facilitation, but may lead to average size at metamorphosis being larger within the population. The consequences of intraspecific competition within aggregations may therefore be different for individuals and populations.

Effective anti-predator defence mechanisms depend on efficient recognition of possible predators. However, nocturnal aerial predators, such as owls, present very few stimuli to enable their detection by potential prey. The most prominent of these are their territorial calls which are believed to provide sufficient stimuli to activate anti-predator defence mechanisms in species heavily predated upon by owls. To test this hypothesis, the behaviour of voles (Microtus socialis), dormice (Eliomys melanurus), jerboas (Jaculus jaculus), and spiny mice (Acomys cahirinus) was analysed during and following exposure to playback of tape recorded calls of the tawny owl (Strix aluco). In response, voles crouched, and retreated to a small burrow present in the test arena; dormice also reduced the distances they travelled in the arena, and spent an increased amount of time around the burrow; jerboas crouched and froze during the playback of the owl call but not thereafter; spiny mice, however, displayed enigmatic behaviour in apparently ignoring the owl calls. The results, which demonstrate an induction of defensive behaviours to recorded owl calls, support the results of others who have examined the effects of exposing wild rodents to live owls.

Predation pressure has long been proposed as a determinant of mammalian social systems. Group size and composition were compared for 121 populations of cercopithecoid primates, from 39 species of 13 genera, living under low, moderate or high predation risk. In confirmation of previous studies, predation risk was found to have a major effect on group size, with populations under high predation pressure living in significantly larger groups than those at lower risk. However, there were differences in social structure between the predation risk categories. Unimale groups were smaller, had fewer females than multimale groups and were infrequently found under conditions of high predation risk. Predation risk had marked effects on the composition of multimale groups. Under conditions of high predation risk there was a disproportionate increase in the number of adult males over that predicted by the number of females present or by group size. At low predation risk there were fewer males than predicted on the basis of female group size. Together, these results suggest that male strategies to monopolize females depend both on the females' grouping patterns and on the needs of both sexes to maximize group size under high predation pressure.

Habitat selection by female Dall's sheep (Ovis dalli dalli) during lambing was studied in interior Alaska, U.S.A., in 1988 and 1989. Selection of habitat changed with the chronology of lambing. During the pre-lambing period, maternal females selected sites with forage and avoided snow-covered areas. During peak lambing, food and steep slopes continued to be selected. Distance to escape terrain was a critical component of habitat selection by females throughout lambing. Maternal bands that ventured farther from escape terrain were in larger groups. Abundance of forage also increased in areas that were farther from this terrain.

Habitat selection by females also differed between years. In 1989, a late spring storm resulted in deep snow and delayed phenology of plants; forage was of lower quality, and the growing season was much shorter in 1989 than in 1988. Births of lambs also occurred later and less synchronously in the second year. Females selected terrain characteristics that were related to avoiding predators in 1988 when forage was more plentiful, but selected sites with forage in 1989 when food was less abundant.

Group size of maternal bands was larger in 1988 than in 1989, and females foraged most efficiently during 1988. Large groups may not have occurred in 1989 because lambs were born asynchronously, preventing cohesive movements of maternal bands with lambs of differing ages.

Both the chronology of lambing and a variable environment affected habitat selection by females. Maternal females made trade-offs between the requirements for forage to meet the high energetic costs of lactation and the risk of predation.

Asaphidion flavipes, A. curtum, and A. stierlini, which are similar in shape and size, were compared for morphological measurements of the head and eyes. The species not only differ in body size but also in the relative length of their antenna, the surface area of their compound eyes, the number and density of their ommatidia, and the structure of their visual space. These differences can be interpreted functionally and correlate well with features of the various habitats in which the species are found.

Sexual size dimorphism in the Cape petrel Daption capense was analysed to improve methods for sexing live birds in field studies. Samples originated from two geographically distant study populations in the Antarctic: Nelson Island, South Shetland Islands (sample N: 83 M, 89 F), and Ardery and O'Connor Islands, Windmill Islands (sample A: 36 M, 27 F). Using single characters with cut points calculated from sexed individuals, about 59–76% (N; best separator tarsus length) and 61–86% (A; best separator tube length) of birds could be assigned to the correct sex. Combination of characters improved performance of sample-specific discriminant functions to a maximum of 84% in the N-sample (five characters) and 95% in the A-sample (four characters). The most useful character sets as well as ranking of individual characters (their weights) differed between samples. At the same time, cross-testing revealed asymmetry in the applicability of sample-specific functions to the other sample. Hence, the method of a generalized discriminant (Auk110: 492–502, 1993) was implemented and tested to develop a species-specific discriminant for the Cape petrel. For all examined character sets, results of their cross-application to the other sample were improved by using character weights estimated from combined samples instead of weights derived only from the original sample. The generalized function (tube length + 1.05*bill depth at tube + 0.72*culmen length + 0.07*wing length) combined with a cut point calculated from a distribution of discriminant scores (assumed mixture of two normal distributions with possibly unequal variances) is suggested as currently the best compromise for sexing Cape petrels in populations for which specific functions are not yet available: comparison with our best sample-specific functions shows a decrease in accuracy by only 1% to 3%. However, examination of other promising characters (head length, bill depth at gonys, mid-toe length) is recommended to improve further a generalized discriminant. In all cases a larger percentage (N: 87–89%, 38 pairs; A: 100%, 27 pairs) of individuals was correctly sexed by within-pair comparison of discriminant scores than according to the sample-specific cut point. No clear evidence for assortative mating with respect to body size has been found in this study. Available biometric data show little evidence for geographical variation in the Cape petrel, which suggests good applicability of generalized sex-discriminants in other populations.

The swamp worm Alma emini subsists in the highly productive waterlogged swamps around the East African Lake Victoria. The soil consists of putrefying plant matter from which gases like methane, carbon dioxide, and hydrogen sulphide are formed and profusely discharged. The interstitial spaces in the soil are generally anoxic and the soil is highly reducing. To survive in such an inimical habitat, Alma has evolved a remarkably unique respiratory strategy. The posterodorsal part of the body, which is well supplied with blood, is regularly converted into a ‘lung’ across which gases are exchanged at the surface or under water. Air and/or water may be entrapped in the ‘lung’ and carried for use (as a source of oxygen and/or a depository of carbon dioxide) during the ensuing underground sojourn. By evolving a unique respiratory potential, Alma emini has been able to flourish in a highly dynamic and virtually anoxic habitat while essentially having a capacity for aerobic biochemistry. Putative indications of cellular adaptations against hydrogen sulphide toxicity were observed, especially in the cells that line the ‘lung’. A. emini presents a good example of nature's tenacious and innovative designs for surviving in severe environments.

The following Applications were published on 18 December 1997 in Vol. 54, Part 4 of the Bulletin of Zoological Nomenclature. Comment or advice on any of these applications is invited for publication in the Bulletin and should be sent to the Executive Secretary (ICZN), c/o The Natural History Museum, Cromwell Road, London SW7 5BD, U.K.

The publisher apologises for the error which occurred on page 450, where an incorrect version of Fig. 1(c) was reproduced. The correct version of Fig. 1(a)–1(d) is printed below.