Blessing the rains down in Africa: spatiotemporal behaviour of the crested porcupine Hystrix cristata (Mammalia: Rodentia) in the rainy and dry seasons, in the African savannah

The assessment of habitat selection and temporal patterns of activity rhythms is paramount for wildlife conservation. Studies on behavioural ecology of wild mammals are particularly challenging in tropical areas, mostly when involving rare or elusive species. Despite being a common species in Italy, the crested porcupine Hystrix cristata is threatened of extinction throughout most of its sub-Saharan range. All available information on the ecology of this species has been collected in Italy, whereas no data is present in the scientific literature on spatiotemporal behaviour of this large rodent in Africa. In this work, we attempted to determine habitat selection and temporal patterns of activity rhythms of the crested porcupine in northern Benin and neighbouring countries, through intensive camera-trapping. We collected a total of 146 records of crested porcupine, 91 in the dry season (October-March) and 55 in the rainy season (April-September). Porcupines used most habitats in proportion to their local availability, while selecting rock outcrop formations (possibly used as shelter sites) and avoiding open areas, wetlands and gallery forests. A mostly nocturnal behaviour was confirmed throughout the year, with some diurnal activity at the start and at the end of the rainy season. The importance of rains in determining birth peak has been also showed, with juvenile individuals always observed at the start and at the end of the rainy season. Full moon always inhibited activity of this large rodent, most likely evolved as an antipredatory behaviour to limit encounters with potential predators (common leopard Panthera pardus, spotted hyaena Crocuta crocuta and honey badger Mellivora capensis) and humans. Poaching pressure towards porcupines in West Africa is strong. Porcupines are killed for the traditional medicine, for their meat and because they are widely considered as a crop pest. This assessment should therefore be used as a basic tool to design conservation plans to preserve this rodent species in its native range.

Seasonal consumption of insects by the crested porcupine in Central Italy

Many herbivorous, granivorous and frugivorous rodents can integrate animal proteins in their diet, still for many of them no information is available on the importance of animal food sources. The crested porcupine, Hystrix cristata, is considered a strictly vegetarian rodent. It may integrate animal proteins through bone-gnawing, while the importance of insects in his diet is poorly known. In this study we assessed the presence of insects in the diet of this rodent in Central Italy by collecting 141 faecal samples along transects in 2016–2020. Hypogeal plant organs were the main component of the diet (absolute frequency = 50.38%; volume = 60.13%). Insects were detected only in 6.8% samples, only in February–March, at the annual birth peak for the crested porcupine. Insect consumption, although occasional, could be linked to the nutritional requirements of this rodent during lactation.

Diet enrichment and the reproductive season of captive Sunda Porcupine (Hystrix javanica F. Cuvier 1823)

This study aimed to extend our current knowledge of Sunda porcupine reproductive biology with emphasis on environmental enrichment and the reproductive season. Tomato and bean sprout feeding able to increase sperm quantity, sperm motility, and viability, as well as increase FSH and estrogen hormone levels. Four pairs of captive Sunda porcupine were used. Two pairs (fed with fresh tomato and bean sprout, enrichment group) and two pairs as control. The birth rate of enrichment group higher (with twin litter per year) than that in control (only one litter per year). It indicated that tomato and bean sprout feeding affect the birth rate in Sunda porcupine. The recent study showed that captive Sunda porcupine births occurred throughout the year, with no more than 1-2 litter per year and are have no interbirth-interval. The birth peak of captive Sunda porcupine occurs between April to August. Biparental activities during birth occurred. However, the female spent 50% of the time with the newborn. There was no courtship behaviour throughout the first two or three months of life of the cub.

Breeding, cub survival, and female reproductive success

Cheetahs are aseasonal breeders, with a weak tendency towards seasonality corresponding to the birth peak in springbok lambs. Cub survival from birth to adolescence was 31.3% compared with 4.8% in the Serengeti. Predation was the major cause of cub mortality in the den, but it was usually impossible to identify the predator. The low survival of cheetah cubs recorded on the Serengeti Plains may be exceptional; in the den, apart from predation, starvation through desertion due to the migratory nature of the prey may sometimes occur; on leaving the den the extremely open landscape may make them especially vulnerable to predation compared with other areas. The mean period between a female losing cubs prematurely, or raising them to independence, until she gave birth again was 3.9 ± 1.6 months. The minimum mean number of cubs raised by a female in her lifetime was 3.5 ± 3.3. This appears to be higher than in the Serengeti.

Factors affecting female reproductive success and the survival of pouch young in the threatened brush-tailed rock-wallaby, Petrogale penicillata

Knowledge of factors affecting the survival of individuals and their reproductive success is essential for threatened species management, but studies assessing these factors are lacking for many threatened rock-wallaby species. In this study we investigated the factors influencing the breeding performance of females and the survival of pouch young in a wild colony of the threatened brush-tailed rock-wallaby. Individuals were trapped between October 2000 and April 2004. More than 50% of the females in the colony were breeding below their full potential and giving birth to only one offspring per year. Most females within the colony bred in synchrony, with a substantial birth peak evident during autumn. Pouch young born in autumn left the pouch during spring and were weaned during summer and autumn when forage was most abundant. Pouch young born during the autumn birth peak or in winter had a substantially higher probability of surviving through to pouch emergence than those born during spring or summer. This study provides demographic parameters that may be used in population models and for comparison with other populations, particularly those that are small and declining. To optimise reproductive success in reintroduction programs, females in good condition and with small pouch young should be released at the end of the wettest season.

Life history and demographics of an island possum

Knowledge of life history and demography is essential for effective management of target species. Here, I describe life history and demographic traits of the common brushtail possum (Trichosurus vulpecula) on Magnetic Island, north Queensland. Data were collected during monthly live-trapping sessions over three years (2001–2004). Density was ~100% higher than reported in most Australian populations, at 5 possums per hectare; losses from the population were more than compensated for by births and immigration. Age-specific survival differed between the sexes: male survival declined earlier and faster than female survival. Males were significantly heavier than females as adults and sexual dimorphism appears to arise through a faster growth rate in males following weaning. Age at maturity in females varied from 1 to 3 years; 61% of females produced their first young at age 2. Males became sexually mature at age 3. Breeding was seasonal, with >50% births occurring in April–May; a smaller birth peak in spring was due to some females producing a second young after they had successfully weaned a first. The Magnetic Island possum population appears to be more similar to New Zealand populations, in terms of their life history and demographics, than to other previously studied mainland Australian populations.

Predation by red fox on European roe deer fawns in relation to age, sex, and birth date

Mortality in radio-marked European roe deer (Capreolus capreolus (Linnaeus, 1758)) neonates was studied during 14 years in a mixed forest–agricultural landscape in Sweden. A total of 233 fawns were marked. Births were synchronized, with 79% occurring during 25 days and a peak between 25 May and 7 June encompassing 62% of the births. Overall mortality was 42%, but in three single years, it exceeded 85%. Predation by red fox (Vulpes vulpes Desmarest, 1820) accounted for 81% of total mortality. The effects of age, sex, and time of birth on the vulnerability to predation were analysed. Fawns born just after the birth peak had the lowest predation risk. Predation rate was highest for the fawns that had the very earliest or the very latest birth dates. Predation thereby seems to strengthen the birth synchrony in roe deer. Contrary to earlier published findings, there was no difference in susceptibility to predation between the sexes. Also differing from earlier findings was that predation rate was highest during the first week of life and declined thereafter almost linearly. The majority of the fawns (85%) were killed before 30 days of age and 98% before 40 days. Different types of landscapes may explain the discrepancies between our study and earlier findings.

The effects of sex, time of birth, and habitat on the vulnerability of roe deer fawns to red fox predation

Red fox (Vulpes vulpes) predation on roe deer (Capreolus capreolus) fawns was studied using radiotelemetry techniques on an island in central Norway. Red foxes killed 48% of the monitored roe deer fawns within 60 days of birth, and mortality from other factors constituted only a minor part (5%) of the total mortality. The predation rate was lower in first week of life than during the subsequent 3 weeks. Male roe deer fawns were four times more susceptible to red fox predation than female fawns. We argue that these results reflect differences in behaviour between the sexes. There were some indications that time of birth may be important in determining vulnerability of fawns to red fox predation, with fawns born during the birth peak suffering more predation than fawns born outside the peak. The type of habitat a roe deer fawn used appeared to influence the probability of being killed by a red fox, and our results supported the hypothesis that hiding is a strategy to avoid predation in dense habitats. Fawns killed by red foxes used open grassland significantly more than surviving fawns, which used woodland to a greater extent.

Population dynamics of the Kaminuriak caribou herd, 1968 - 1985

The Kaminuraik caribou herd apparently declined from about 120 000 animals in 1950 to 63 000 in 1968. Beginning in 1968 documentation of herd trend was based on the estimate of the number of breeding (pregnant and post-partum) females on the calving ground during the birth peak. It appeared as if we understood the basic population processes responsible for the decline when we correctly predicted a drop from 14 800 breeding females in 1977 to 13 000 in 1980. However a three-fold increase, to 41 000 breeding females in 1982, and continued growth thereafter, was unanticipated. Most of that increase must have resulted from an immigration of cows to the herd's traditional calving ground around Kaminuriak Lake, although increased birth rates, and increased survival rates also contributed to herd growth. Immigrant cows probably came from the northeastern mainland of the NWT

Season of Birth in the Population of Norway, with Particular Reference to the September Birth Maximum

The monthly number of births in Norway fluctuates between a maximum in January–May and a minimum in October–December. This cyclic seasonality is assumed to be of biological origin, but indirectly it is influenced by social factors and consequently tends to vary a great deal. There is a secondary birth maximum in September, corresponding to a peak of conceptions during the traditional festivities around Christmas and New Year. It is shown that this maximum is much less variable within the country studied, though it probably varies from one country to another in relation to the impact of the mid-winter traditions.The January–May birth maximum is known to be higher in schizophrenia than in the general population, while no such difference is observed in Norway for the September birth peak. It is felt that there is a fundamental difference between the two birth maxima and a corresponding difference between schizophrenic patients and the general population. Minimal paranatal brain damage of seasonal origin is suggested as an explanation.