bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of season, habitat and research techniques on diet composition of roe deer (Capreolus capreolus): a review
Authors: Cornelis Johnny , Casaer Jim , Hermy Martin 
Published: February 2006

AbstractWe summarize the information on the diet of roe deer Capreolus capreolus found in 33 European studies. After giving a short overview of the differences between the existing studies, we compare the information for each season. We submit the information, summarized in a matrix of 83 cases on 10 food groups, to a detrended correspondence analysis (DCA) and a two‐way indicator species analysis (TWINSPAN). We calculate weighted averages grouping the information by season, habitat, research method and their cross‐products. The weighted averages are also used as input for a multivariate ratio analysis. Since the available food items dictate the possible diet composition we further investigate the influence of the habitat on the reported food selection. The influence of season on the diet composition is compared with the effect of the habitat, and other factors such as research method and geographical location of the study site. The review shows that there is relatively little seasonal variation in the diet composition, which is more closely correlated to the habitat than to the season.
A mitochondrial DNA perspective on the evolution of Iberian Discoglossus (Amphibia: Anura)
Authors: Garcí‐París M. , Jockusch E. L. 
Published: February 2006

AbstractSequences of a mtDNA gene, cytochrome b, were used to generate a phylogenetic hypothesis for the evolution of Iberian archaeobatrachian frogs of the genus Discoglossus. Results from the inferred phylogenetic branching pattern and the sequence divergence among species and populations support the following: (1) the two endemic species from Iberia, D. galganoi and D. jeanneae are sister taxa and are reciprocally monophyletic with respect to their mtDNA; (2) the geographic distribution of these two morphologically cryptic species differs considerably from previous expectations. D. galganoi is limited to the metamorphic granitic and shale substrates of western Spain and Portugal, while D. jeanneae extends over the limestone and gypsum substrates of most of eastern Spain from the Strait of Gibraltar to the Pyrenees; (3) sequence divergence between D. galganoi and D. jeanneae averages 8.6%, suggesting that the two lineages diverged before the Mio–Pliocene boundary. We suggest that these lineages were isolated by the opening of the Betic Strait and that isolation has been maintained until recently by the Guadalquivir River Basin; (4) all specimens of D. jeanneae, from the central Pyrenees in the north to the southern end of the Iberian Peninsula have nearly identical cytochrome b haplotypes, clear evidence of a rapid relatively recent (Late Pleistocene–Quaternary) expansion of the species; (5) populations of D. pictus from northeastern Spain are highly divergent from all other Discoglossus studied and do not fall within the Iberian clade.
Conflicts and interactions among reproduction, thermoregulation and feeding in viviparous reptiles: are gravid snakes anorexic?
Authors: Gregory Patrick T. , Crampton Lisa H. , Skebo Kristina M. 
Published: February 2006

AbstractConstraints on time and energy suggest that animals often will have to forgo one activity in favour of another. In the field, gravid garter snakes, Thamnophis elegans, eat little or nothing, especially late in pregnancy. In addition, they spend considerable time basking, presumably to aid development of their progeny. Apparently, therefore, a conflict exists between feeding and behaviours related to gestation. Alternatively, low feeding levels in the field might reflect reduced ability to catch food while gravid, or anorexia, attributable either to reduced space in the gut or to physiological suppression of appetite. In this study, by supplying abundant food in the laboratory, we test the hypothesis that gravid females are anorexic; we also examine the interactions among feeding, thermoregulation and reproductive condition. Typically, gravid females, whether fed or not, spent most of their time at the warm end of a gradient, as did fed non‐gravid snakes; unfed non‐gravid females spent significantly less time at the warm end. However, gravid snakes, even when presented with food ad libitum, ate less than non‐gravid snakes, suggesting that they are anorexic while pregnant. Feeding and thermoregulatory behaviours of gravid females changed around the time of parturition (increased feeding, reduced warming rate). Comparable changes are seen in animals in the field, and are correlated with changes in movement pattern. Evidently, the tendency to eat little food is carried over into the laboratory, even when apparent proximate causes of the behaviour are removed. Although we cannot distinguish clearly between the two potential causes of anorexia, the evidence slightly favours physiological suppression of appetite. Physiological suppression of appetite while gravid would ensure that the urge to forage rather than thermoregulate does not diminish the chances of present reproductive success. By contrast, non‐gravid snakes, faced with a shortage of food, lower their body temperature and reduce their metabolic costs.
The structure of the foregut and midgut of nymphs, subimagos and imagos of Cloeon dipterum (Ephemeroptera) and the functions of the gut of adult mayflies
Authors: Harker Janet E. 
Published: February 2006

AbstractThe anatomy of the gut and the fine structure of the foregut and midgut of the nymphal, subimaginal and imaginal stages of C. dipterum are described. A new description is given of the nymphal foregut–midgut junction and its relationship to peritrophic membrane formation. Although the mouthparts are lost at the end of the nymphal stage, and the structure of the gut undergoes extensive and often degenerative changes both during and after each of the moults to subimago and imago, the structure of the subimaginal and imaginal gut nevertheless suggests that the gut is still performing some active function during both adult stages. This is also suggested by the persistence in subimagos and imagos of rhythmical waves of midgut contraction, an energetically expensive process for an animal which has ceased to feed. Although a very occasional uptake of fluids by imagos has been observed, it has been shown, by the use of a fluorescent stain, that fluid which disappears from the mouth region is most frequently being spread as a very thin film over the body surface rather than entering the gut. Frequency of midgut contraction has been measured in resting subimagos and imagos of C. dipterum and C. simile, in imagos of C. dipterum during and after being held in a dry atmosphere, in ovipositing imagos of C. dipterum, in ejaculating male imagos of C. simile and Ecdyonurus venosus, and after successive bouts of flying by E. venosus. Previous claims that the midgut contractions either control or affect oviposition and sperm ejaculation have not been substantiated. The possibility of a key relationship between the midgut contractions and the need for rapid transport of metabolities is discussed.
Sprint performance of phrynosomatid lizards, measured on a high‐speed treadmill, correlates with hindlimb length
Authors: Bonine Kevin E. , Garland Theodore 
Published: February 2006

AbstractWe measured sprint performance of phrynosomatid lizards and selected outgroups (n= 27 species). Maximal sprint running speeds were obtained with a new measurement technique, a high‐speed treadmill (H.S.T.). Animals were measured at their approximate field‐active body temperatures once on both of 2 consecutive days. Within species, individual variation in speed measurements was consistent between trial days and repeatabilities were similar to values reported previously for photocell‐timed racetrack measurements. Multiple regression with phylogenetically independent contrasts indicates that interspecific variation in maximal speed is positively correlated with hindlimb span, but not significantly related to either body mass or body temperature. Among the three phrynosomatid subclades, sand lizards (Uma, Callisaurus, Cophosaurus, Holbrookia) have the highest sprint speeds and longest hindlimbs, horned lizards (Phrynosoma) exhibit the lowest speeds and shortest limbs, and the Sceloporus group (including Uta and Urosaurus) is intermediate in both speed and hindlimb span.
Attacks to humans and domestic animals by the southern cassowary (Casuarius casuarius johnsonii) in Queensland, Australia
Authors: Kofron Christopher P. 
Published: February 2006

AbstractThe southern cassowary Casuarius casuarius johnsonii is endemic to the tropical rainforests of north‐eastern Queensland, Australia. This species is Australia's largest bird and holds a reputation for being dangerous. Cassowaries and ostriches are the only birds world‐wide that have caused human deaths by physical attack. Incidents occur every year in Queensland, most at Mission Beach (110 km south of Cairns) and Lake Barrine (39 km south‐west of Cairns), but previously also at Mount Whitfield in Cairns. The incidence of cassowary attacks in Queensland is reviewed. Data were obtained for 221 cassowary attacks, of which 150 were against humans, 75% of these by cassowaries fed previously by people. The feeding of cassowaries appears to change their natural behaviour, making them bold and aggressive. Victims were chased or charged in 71% of the incidents, and kicked in 15%. Less frequent actions included pushing, pecking, jumping on, butting with the head and snatching food. The cassowaries appeared to be expecting or soliciting food from humans (73% of the incidents), defending food (5%), and defending themselves (15%) or their chicks or eggs (7%). Contrary to popular belief, jogging did not incite cassowaries to attack. Although cassowaries should not be considered dangerous, they can cause serious injuries. Seven attacks against humans resulted in serious injuries (puncture wounds, lacerations, broken bone) and subsequently one death, caused by cassowaries kicking or jumping on victims. In the single fatal attack, the victim was trying to kill the cassowary. Four of the seven seriously injured victims were crouching or lying on the ground.
The red fox (Vulpes vulpes) in Saudi Arabia: loose‐knit groupings in the absence of territoriality
Authors: Macdonald D. W. , Courtenay O. , Forbes S. , Mathews F. 
Published: February 2006

AbstractAdaptations to extreme environmental conditions were investigated in a detailed study of red foxes Vulpes vulpes inhabiting a desert region of Saudi Arabia. Forty‐two adult foxes were live‐trapped during 3 years of field work. In contrast to red foxes studied in other areas, no strict territoriality was observed in this population. Although close interaction (separation < 1 m) was more common between members of the same, rather than different, social groups, medium distance interactions were similar. Further, intra‐group encounters were much less common than for foxes in the U.K., and foxes did not avoid each other at territory boundaries. All foxes used food‐rich sites associated with human activity, and aggregations of up to four foxes were regularly seen in these areas. It is suggested that the combination of an extremely harsh environment, with spatially and temporally variable food supplies, leads to the formation of loosely knit social groups. Saudi Arabian red foxes followed Bergmann's rule in being considerably smaller than those found in cooler areas. They also had a lighter coloured pelage than red foxes typical of Europe and North America. These morphological differences may represent adaptations to the low availability of food and rest sites in the desert.
Pupping season, perinatal sex ratio and natality rates of the Mediterranean monk seal (Monachus monachus) from the Cabo Blanco colony
Authors: Gazo Manel , Layna Jorge F. , Aparicio Fernando , Cedenilla Miguel Angel , González Luis Mariano , Aguilar Alex 
Published: February 2006

AbstractPupping seasonality, annual pup production, reproductive rate and sex ratio at birth were determined for the Mediterranean monk seal Monachus monachus colony at Cabo Blanco, the only surviving population of the species which still shows a colony structure. Data were collected by means of a monitoring programme that operated continuously in the main reproductive areas of the population during the period March 1993–May 1997. Most (84%) of the pups observed were born in two caves separated by a short distance. Although both caves were used by females to bear the pups, preferences greatly fluctuated from season to season with no apparent trend. Reproduction occurred throughout the year with a small peak of births in October. This unusual lack of seasonality is associated with the low latitudinal location of the colony and the effect of the upwelling that provides constant food throughout the year. The neonatal sex ratio did not differ significantly from 1:1 and the estimated annual productivity ranged from 44–58 pups. Taking into account population numbers, the annual birth rates were estimated to range from 0.3 to 0.43 pups per reproductive female, an extremely low rate when compared to other pinniped populations, particularly those of a similar size. Such low rates may be either an evolutionary determined characteristic of the species or a demographic consequence of the low population density over the last few centuries. Coupled with high pup mortality rates, this may account for the observed non‐recovery of the population.
Plumage polymorphism of red‐footed boobies (Sula sula) in the western Indian Ocean: an indicator of biogeographic isolation
Authors: Le Corre Matthieu 
Published: February 2006

AbstractThe pantropical red‐footed booby Sula sula is one of the most polymorphic seabirds. In the Indian Ocean most extant colonies hold white morph adults except on Europa Island (southern Mozambique Channel), where adults are of the white‐tailed brown morph and on Tromelin Island (western Indian Ocean), where one‐third of the birds are of the white‐tailed brown morph and two‐thirds are of the white morph. On Tromelin, the morph ratio has remained constant over the last 40 years. An extinct colony (Glorieuses Islands, northern Mozambique Channel) once supported a white‐tailed brown morph population. These results suggest that the colonies of the western Indian ocean do not constitute one great gene pool where exchanges occur, but are isolated at various degree from each other. Particularly, the population of Europa is the only current population of the Indian Ocean constituted almost entirely of white‐tailed brown morph, suggesting that it is isolated from other nearby colonies. Possible causes of isolation are discussed in the light of oceanic features of the Mozambique Channel. Although further studies are needed to understand the adaptive significance of plumage coloration in red‐footed boobies, I suggest that white‐tailed brown morph at Europa may act as a defensive camouflage against kleptoparasitism by great frigatebirds Fregata minor and brown skuas Catharacta antarctica.
Variation in daily activity of the free‐living Eurasian lynx (Lynx lynx) in Białowieża Primeval Forest, Poland
Authors: Schmidt Krzysztof 
Published: February 2006

AbstractThe pattern of daily activity of the Eurasian lynx Lynx lynx L. was studied by radio‐telemetry in the Białowieża Primeval Forest (eastern Poland). Radio‐tracking of 18 lynx was done by 24‐h continuous observations and by sampling on a daily basis. Lynx were active mostly at night. There was generally one peak of activity between 15:00 and 07:00 which, however, decreased slightly between 20:00 and 22:00. On average, lynx were moving for 6.5 h/day. In males, 73% of locomotory activity occurred at night, whereas females were active as long during the daylight as during the night. Movement bouts of females were shorter than those of males (1.1 h vs 2.1 h) but more frequent (4.2 vs 3.0 bouts/day). General patterns of activity of females with and without kittens were similar. However, females with kittens were active twice as long per day than non‐reproducing females. In May–August (intensive care for kittens), reproducing females were active 26% longer than in September–April. Non‐reproducing females showed the opposite pattern; they were active 60% less in May–August compared with September–April. Locomotory activity of adult males was 30–70% longer in January–March (mating season) than in other seasons. The pattern of lynx activity was shaped predominantly by searching for and consuming large prey. The lynx were active for the longest time during the days when they searched for prey but made no kill (12.5 h/day on average) and for the shortest time on the first day after killing a deer (1.6 h/day). Their moving activity increased steadily in the following days, reaching 6.8 h/day on the fourth day of consuming a killed deer. Ambient temperatures and rainfall did not significantly affect lynx activity, but there was little movement most of the time in heavy rain, and all day when the temperature was above 30 °C.
Factors influencing the selection of roost cavities by a temperate rainforest bat (Vespertilionidae: Chalinolobus tuberculatus) in New Zealand
Authors: Sedgeley Jane A. , O'Donnell Colin F. J. 
Published: February 2006

AbstractThe selection of roost cavities by the threatened New Zealand long‐tailed bat Chalinolobus tuberculatus was examined in unmodified temperate southern beech Nothofagus rainforest in Fiordland, New Zealand. We radio‐tracked 73 bats during spring–autumn of 1993–1997 to 155 day roosts, all of which were in trees. One hundred and forty‐nine roosts were in cavities: 84 in live trunks, 33 in dead trunks, 32 in large branches (seven in dead branches, 25 in live); and the remaining six (occupied by solitary bats) were beneath loose bark. We compared characteristics of the 84 roost cavities in live trunks with 57 random available cavities also in live trunks. Cavities used by C. tuberculatus were not a random subset of available cavities. In comparison to available cavities, bat roosts were all located in knot hole cavities, were high from the ground, and had little surrounding vegetation. All roosts were dry inside. Bats used a higher proportion of cavities which had medium sized entrances and internal cavities, and thicker cavity walls. A logistic regression model incorporating nine cavity variables classified roost and available cavities correctly 97% and 91% of the time, respectively. Distance to the nearest vegetation, cavity condition (wet or dry inside), height from the ground, and to a lesser extent internal cavity height, explained significant proportions of the variation between roost and available cavities. Bats changed roost sites virtually every day and it appeared that suitable cavities were abundant in the unlogged forests of the study area. It is unlikely that modified forests and forests managed for timber production contain such a large pool of potential roosting cavities.
Factors affecting nesting beach selection by loggerhead turtles (Caretta caretta): a multiple regression approach
Authors: Kikukawa Akira , Kamezaki Naoki , Ota Hidetoshi 
Published: February 2006

AbstractBased on data obtained from 3 years' fieldwork in Okinawajima and adjacent islands of the central Ryukyus, Japan, various physical and human‐related beach characters were assessed for their relative influence on beach selection by nesting sea turtles using multiple regression analysis. Of the 23 characters considered, sand softness (measured by a specially designed tool) (positive), distance from the nearest human settlement (positive), presence of lagoon (positive), beach length (negative), and beach height (positive) were selected as influential variables in descending order. Explanations were attempted for such results in the light of correlates of these beach characters with natural and artificial factors that are believed to impact the nesting success of female sea turtles.
Skeletochronology and mark–recapture assessments of growth in the North African agamid lizard (Agama impalearis)
Authors: El Mouden El Hassan , Znari Mohammed , Brown Richard P. 
Published: February 2006

AbstractPatterns of growth were studied between 1993 and 1996 in a population of Bibron's agama Agama impalearis from an arid area in the central Jbilet Mountains, western Morocco. Non‐linear regressions were used to model snout–vent lengths (SVL) and body masses of individuals caught during 1993–94 against skeletochronology age estimates. The overlap between male and female asymptotic SVLs (A) was negligible demonstrating sexual dimorphism, although there was no evidence of differences in characteristic growth rates (k) between sexes (males: A= 119.43 ± 2.29 mm and k= 0.849 ± 0.09 [month−1], females: A= 108.59 ± 3.19 mm and k= 1.079 ± 0.162 [month−1]). Asymptotic body mass differed substantially between sexes (males: 71.2 ± 3.1 g, females: 45.8 ± 4.2 g), but corresponding characteristic growth rates were similar (0.753 ± 0.339 and 0.789 ± 0.623 [month−1], respectively). The mark–recapture method provided generally higher and more reliable asymptotic size estimates (using the logistic‐by‐length non‐linear regression model) than the skeletochronology‐based estimates. Growth parameters were also estimated on an individual year basis. Only male characteristic growth rate showed a significant year‐to‐year variation (0.010 ± 0.006 to 0.024 ± 0.007 [day−1]), although this may have been due to a lack of statistical power. Annual variation in the absolute growth rate was detected only in hatchlings (0.087 ± 0.018 to 0.273 ± 0.132 mm.day−1) and adult males (0.089 ± 0.030 to 0.206 ± 0.100 mm.day−1).
Intraguild predation may explain an amphipod replacement: evidence from laboratory populations
Authors: Dick Jaimie T. A. , Montgomery W. Ian , Elwood Robert W. 
Published: February 2006

AbstractIn a laboratory experiment that permitted both observations of the behaviour of individuals and the monitoring of small populations, the role of ‘intraguild predation’ in the elimination of the freshwater amphipod Gammarus duebeni celticus by the introduced G. pulex was examined. Over 18 weeks, deaths in single and mixed species replicates were monitored. Rates of ‘mortality’ (deaths not due to cannibalism or predation) did not differ between the species. Gammarus d. celticus, however, was more cannibalistic than G. pulex and, in both species, males were more often cannibalized than females. In mixed species replicates, the mean proportions of animals preyed upon did not differ among replicates with differing starting proportions of the two species, nor was there a difference between the sexes in numbers preyed upon. G. pulex, however, preyed more frequently on G. d. celticus than vice versa, and this became more pronounced over time. In 87% of mixed species replicates, G. pulex eliminated G. d. celticus. The results support the proposition that intraguild predation may be the primary mechanism whereby G. pulex rapidly replaces G. d. celticus in freshwater. Integrating behavioural observations with population level monitoring may thus link pattern and process in behaviour and ecology.