The ecology of Maesopsis eminii Engl. in tropical Africa

Maesopsis eminii is referred to as one of the most widely distributed African tree species. However, its occurrence in Africa has never been mapped and little is known as to how this species can sustain in different environments. To gain insight into Maesopsis’ ecology, we (i) made a synthesis of its functional trait data from the literature, (ii) investigated phenological patterns using data on four M. eminii trees from Yangambi, DR Congo, (iii) assessed an empirical provenance trial from Uganda on 600 Maesopsis trees and (iv) synthesized geo‐referenced point location maps of Maesopsis entailing WorldClim precipitation and temperature and FAO soils, rainfall and ecological zones for Africa. We found M. eminii to straddle the equator equidistantly in terms of latitude (10.97°N and 10.98°S) covering five forest types where twenty soil types and variable rainfall regimes support complex plant biodiversity. Maesopsis eminii was, however, largely concentrated in the tropical rainforest ecosystem which contains fertile Orthic Ferralsol soils. More than 97% of the point locations were found where annual precipitation was >1000 mm, and 82% occurred where average annual temperature was 22–28°C. Its functional traits, phenology and provenance trial findings explained its occurrence in Africa.     

Diet of Adult and Nestling Scarlet Macaws in Southwest Belize,Central America1

Scarlet Macaw diet was determined during the breeding season of February–June 1998. Macaws were primarily granivorous, exhibiting a narrow diet during the dry season, with low variety of food items in adult and nestling diets. Seeds of Cnidoscolus spp. and Schizolobium parahybum, tree species characteristic of floodplain forest, were predominant in nestling diets, and may provide protein‐rich food resources. River floodplains provided important nest sites and food resources for Scarlet Macaws during the breeding season.     

Diet of sympatrically breeding Southern Carmine Bee-eater Merops nubicoides and White-fronted Bee-eater Merops bullockoides

The Southern Carmine Bee-eater Merops nubicoides and White-fronted Bee-eater Merops bullockoides are insectivore, cavity-nesting bird species, both of which occur in the Zambezi Region, north-eastern Namibia. I examined there the diet composition of these species by an analysis of prey remnants. The Southern Carmine Bee-eater chick's diet consisted of exclusively insects, represented by seven orders. The most numerous were orthopterans and beetles (40.9% and 26.1%, respectively; n = 582 prey items). Hymenopterans (18.7%) and bugs (12.9%) supplemented the diet, whereas dragonflies (Odonata) and moths (Lepidoptera) were preyed only occasionally. In the diet of the White-fronted Bee-eater, nesting at the same site, beetles were the most important prey (81.2% of all 101 prey items identified), with scarabaeids comprising more than half of the beetle diet. In comparison with the White-fronted Bee-eater, a lower proportion of beetles, but much larger proportion of orthopterans were recorded in the diet of the Southern Carmine Bee-eater. In both bee-eater species, hymenopterans appear to be less important than was expected. The essential difference in the proportion of main prey groups recorded in Southern Carmine and White-fronted Bee-eaters breeding at the same site may represent a shift in food niche due to both temporal segregation in breeding, and differences in food preferences (feeding sites).     

The breeding biology of the White-spectacled Bulbul,Pycnonotus xanthopygos,at the northwestern edge of its distribution range

The White-spectacled Bulbul, Pycnonotus xanthopygos, is an abundant and possibly invasive species in Turkey, where it has gradually expanded its distribution and breeding range in both western and southeastern directions. This study focused on its breeding biology, which is still poorly known. The breeding activity extends from February until September. The preferred nesting areas are mainly gardens and maquis groves, where 24 different nesting tree species have been identified. The clutch size is 3.3 ± 0.8 eggs per pair, nesting success 68%, hatching success 94%, fledgling success 95%, and overall breeding success 89%. While nesting success differs significantly between the years, we found no significant differences in hatching, fledging, and overall breeding success between the years studied. Despite favourable climatic conditions in the Mediterranean region, the species makes only one brood per year in a relatively extended breeding season extending over seven months, and has a relatively a high reproduction rate per nest.     

Lesser Scaup Breeding Probability and Female Survival on the Yukon Flats,Alaska

ABSTRACT Information on the ecology of waterfowl breeding in the boreal forest is lacking, despite the boreal region's importance to continental waterfowl populations and to duck species that are currently declining, such as lesser scaup (Aythya affinis). We estimated breeding probability and breeding season survival of female lesser scaup on the Yukon Flats National Wildlife Refuge, Alaska, USA, in 2005 and 2006. We captured and marked 93 lesser scaup with radiotransmitters during prelaying and nesting periods. Although all marked lesser scaup females were paired throughout prelaying and incubation periods, we estimated breeding probability over both years as 0.12 (SE = 0.05, n = 67) using telemetry. Proportion of lesser scaup females undergoing rapid follicle growth at capture in 2006 was 0.46 (SE = 0.11, n = 37), based on concentration of yolk precursors in blood plasma. By combining methods based on telemetry, yolk precursors, and postovulatory follicles, we estimated maximum breeding probability as 0.68 (SE = 0.08, n = 37) in 2006. Notably, breeding probability was positively related to female body mass. Survival of female lesser scaup during the nesting and brood-rearing periods was 0.92 (SE = 0.05) in 2005 and 0.86 (SE = 0.08) in 2006. Our results suggest that breeding probability is lower than expected for lesser scaup. In addition, the implicit assumption of continental duck-monitoring programs that all paired females attempt to breed should be reevaluated. Recruitment estimates based on annual breeding-pair surveys may overestimate productivity of scaup pairs in the boreal forest.     

Dietary changes of Mediterranean Shags Phalacrocorax aristotelis desmarestii between the breeding and post-breeding seasons in the upper Adriatic Sea

Capsule?Shags move between breeding and non-breeding areas and this is associated with a significant change in diet.

Aims?To determine whether the diet of Shags nesting on islets off the Croatian coast is the same as their diet after the post-breeding move to the Gulf of Trieste.

Methods?Diet was determined by the analysis of 611 regurgitated food pellets.

Results?A total of 23 988 prey items were identified in the sample of pellets. Post-breeding Shags in the Gulf of Trieste focused on demersal and relatively immobile Gobiidae (81.5% by number, 87.1% by biomass). The most frequent prey species was Gobius niger (70.8% by number). In the breeding season at Oruda island, Croatia, the diet was more varied. Breeding Shags fed on bentho-pelagic, mobile prey such as Atherina boyeri (28.4% in frequency), Serranus hepatus (16.1%) and Crenilabrus tinca (12.0%), while Gobiidae had a dietary frequency of only 18.1%. With respect to biomass the most important prey were Crenilabrus tinca (19.0%) and Serranus hepatus (18.4%).

Conclusion?We suggest that the movement of Shags within the Adriatic Sea is driven by dietary requirements. Most previous studies of Shag diet have shown that Shags tend to have a more specialized diet during the breeding season, concentrating upon demersal prey species. However, we have found that birds breeding at the Croatian study colony show dietary diversity. We suggest that lack of dietary specialization is a facultative response to local prey abundance, and is probably the result of over-fishing of demersal species in the areas around the breeding locations in which the birds find suitable sites and are little disturbed by human activity. Shags may move immediately after breeding to the Gulf of Trieste because demersal species are likely to be more abundant there. As a consequence, the diet becomes more specialized and is then more similar to the diet of other populations of Shags.     

Breeding phenology and success of the Common Snipe Gallinago gallinago in the Azores

ABSTRACT

Capsule: In comparison to other regions, the Common Snipe Gallinago gallinago in the Azores starts to display earlier and for a longer part of the year, but the laying period, although it starts earlier, does not seem to differ much from that observed elsewhere. Nesting success seems similar to that observed in other populations.

Aims: This study aimed to infer the breeding phenology, characterize some basic breeding parameters, and quantify nesting success in a sedentary, and data deficient population of the Common Snipe.

Methods: Counts of Common Snipe in display (2014) and searches of nests and broods (2011 and 2014) were conducted during the breeding season on São Jorge Island in the Azores. Additional data collected on São Miguel Island was also considered. Nests were monitored to assess nest survival.

Results: The species was seen in display between January and August, and the laying period spanned between early March and late June. The probability of survival during the nesting period was 0.55 (n?=?24; 95% – confidence limits: 0.38–0.80), and desertion was the main cause of failure.

Conclusions: The best period to assess the population of Common Snipe in the Azores is during April, when the displaying activity is at its maximum. The species is very sensitive to disturbance during the nesting and rearing periods, thus managers should avoid interventions in the habitat between March and July to reduce disturbance.     

Factors Affecting Daily Nest Survival of Burrowing Owls Within Black-Tailed Prairie Dog Colonies

ABSTRACT Identifying environmental parameters that influence probability of nest predation is important for developing and implementing effective management strategies for species of conservation concern. We estimated daily nest survival for a migratory population of burrowing owls (Athene cunicularia) breeding in black-tailed prairie dog (Cynomys ludovicianus) colonies in Wyoming, USA. We compared estimates based on 3 common approaches: apparent nesting success, Mayfield estimates, and a model-based logistic-exposure approach. We also examined whether 8 intrinsic and extrinsic factors affected daily nest survival in burrowing owls. Positive biases in apparent nest survival were low (3–6%), probably because prior knowledge of nest locations and colonial behavior among nesting pairs facilitated discovery of most nests early in the nesting cycle. Daily nest survival increased as the breeding season progressed, was negatively correlated with ambient temperature, was positively correlated with nest-burrow tunnel length, and decreased as the nesting cycle progressed. Environmental features were similar between failed and successful nests based on 95% confidence intervals, but the seasonal midpoint was earlier for failed nests (31 May) compared to successful nests (15 Jun). The large annual variation in nest survival (a 15.3% increase between 2003 and 2004) accentuates the importance of multiyear studies when estimating reproductive parameters and when examining the factors that affect those parameters. Failure to locate and monitor nests throughout the breeding season may yield biased estimates of nesting success in burrowing owls (and possibly other species), and some of the variation in nesting success among years and across study sites may be explained by annual and spatial variation in ambient temperature. Any management actions that result in fewer prairie dogs, shorter burrow lengths, or earlier nesting may adversely affect reproductive success of burrowing owls.     

Nest niche dynamics of Meyer's Parrot Poicephalus meyeri in the Okavango Delta,Botswana

Meyer's Parrot Poicephalus meyeri is the only cavity-nesting bird species that breeds during winter in the Okavango Delta. This is facilitated by exclusive access to arthropod larvae incubating inside and feeding on fruits and pods in their diet. To minimise predation risk and overcome low overnight temperatures they have specialised, non-random nest cavity preferences that restrict them to 4.5% of the available nest cavities in the study area. Here we evaluated the nest niche of Meyer's Parrot by studying the nest tree preferences and ecological context of all nest cavities to determine factors that may restrict breeding success in disturbed or altered habitat. Although specific nest tree preferences were significantly different between host tree species, Meyer's Parrot preferred trees greater than 14 m in height that were in relatively poor condition (e.g. portion of the canopy dead). A comparison of nest tree characteristics (n = 75) and the availability of these tree specifications in a representative sample of the different habitat types (n = 1 129) within the sample area indicated that Meyer's Parrot are dependent on riverine forest, Acacia-Combretum marginal woodland and dry mopane woodland for nesting opportunities. Disturbance to hardwood trees by African elephants Loxodonta africana and fungal attack (e.g. Coriolus versicolor) are likely important dynamics in supporting healthy Meyer's Parrot populations and cavity-nesting bird communities.     

Direct and indirect effects of an insect outbreak increase the reproductive output for an avian insectivore and nest‐cavity excavator,the red‐breasted nuthatch Sitta canadensis

Community‐wide food pulses may ameliorate food constraints but may also result in increased competition for other resources and predation rates. In cavity‐nesting vertebrate communities, where the availability of tree cavities can limit reproduction and the reuse of cavities can increase nest predation by squirrels, excavators may maximize their fecundity by creating new cavities in competitor‐ and predator‐rich habitats that undergo food pulses. The reproductive cost associated with excavation (i.e. increased energy allocation early in the breeding season that often delays laying and thereby reduces clutch size), may be reduced if food pulses allow for a longer breeding season and larger clutches. A large‐scale mountain pine beetle Dendroctonus ponderosae outbreak that occurred during our long‐term study (1995–2009) provided a natural food supplementation experiment across 27 sites in British Columbia, Canada. We examined the effects of a reduction in food constraints accompanied with increases in excavation rates, conspecific density and nest predation risk on the fecundity of a facultative excavator, the red‐breasted nuthatch Sitta canadensis. We found a total of 420 nests in tree cavities. Nuthatch clutch sizes ranged from two to nine eggs, and broods from one to nine fledglings per nest. Later clutches were larger at sites and in years with high beetle abundance (mean clutch size of six eggs did not decline later in the season), second broods were produced in outbreak years (usually only one nesting attempt/normal year), and the number of fledglings per successful nest increased with increasing beetle abundance and nuthatch densities, but declined with increased squirrel densities. Since fecundity did not differ between new and reused cavities, the costs and benefits of excavation versus cavity reuse may be neutralized for nuthatches during strong resource pulses. Overall, the beetle outbreak reduced food constraints for nuthatches and provided alternate food for nest predators, allowing increased annual fecundity.     

蓝冠噪鹛繁殖期生境选择特征分析

2013年至2015年每年4—7月,在江西婺源境内对蓝冠噪鹛繁殖小群进行调查。观察并测量其繁殖地斑块海拔,距山地、水源及干扰源的距离,计算斑块面积、周长及形状指数,并在每个繁殖斑块的4个方向5km以外选取同样植被类型的对照斑块,比较繁殖斑块与对照斑块在以上7个因子的差异。结果表明繁殖斑块海拔,距山地距离和距干扰距离显著小于对照斑块。说明在斑块尺度上,蓝冠噪鹛繁殖期倾向于选择低海拔阔叶林,且在离山地更近的村庄附近繁殖,这可能与食物丰富和天敌较少有关。在微生境尺度,选择繁殖点B在巢区及同一片阔叶林中无噪鹛筑巢的对照区进行10个生态因子的测量,并用资源选择函数以及Vanderploeg和Scavia选择系数进行分析。资源选择函数结果表明草本密度、草本高度在微生境尺度对蓝冠噪鹛生境选择贡献最大;而Vanderploeg和Scavia选择系数结果表明蓝冠噪鹛喜在胸径较粗(40—80cm)的朴树、枫杨和枫香3种树上筑巢,筑巢偏好树高20m以上及草本盖度较高(60%—90%)的生境。综合两种分析结果,在微生境尺度蓝冠噪鹛对筑巢树种及高度具有选择性,对巢区隐蔽性有所要求,巢下草本情况可以反映昆虫等食物资源状况,说明蓝冠噪鹛繁殖期偏好在食物相对丰富的区域筑巢。     

Resource partitioning in sympatric arctic-breeding geese: summer habitat use, spatial and dietary overlap of Barnacle and Pink-footed Geese in Svalbard

The spatial, habitat and dietary overlap of two breeding goose species was studied in Sassendalen, Svalbard, in summer 2003 based on abundance within 500 × 500‐m grid squares and faecal diet analyses during pre‐breeding, nesting and post‐hatching periods. More than half of all Pink‐footed Geese Anser brachyrhynchus occurred in the absence of Barnacle Geese Branta leucopsis during nesting and post‐hatching periods compared to c. 20% when concentrated by pre‐breeding snow cover. In contrast, only 5% of Barnacle Geese were observed in the absence of Pink‐footed Geese pre‐breeding, 15% during nesting, and 35% post‐hatching. Among six defined habitat types, Barnacle Geese resorted more to ‘upland’ habitats during pre‐breeding and nesting and to lowland lakes post‐hatching when compared to Pink‐footed Geese. Although Pink‐footed Geese showed less change in seasonal habitat preference, many shifted to the river valley bottom post‐hatching, giving access to open water (predator avoidance) and lush green vegetation (foraging for goslings). The smallest extent of distributional overlap between the two species occurred post‐hatching, but each species was also highly restricted by snow cover during pre‐nesting. The greatest extent of overlap in distribution and diet occurred during incubation, when large dietary variation between different breeding valleys reflected local food availability around nests (probably a result of nest‐site preference rather than food selection per se). Whether this means that increased interactions within and between the two goose species with future increases in local density are most likely to be manifest at this stage of the summer is impossible to determine without knowledge of available food resources and manipulative experiments. More detailed investigations of the effects of foraging by both species on plant structure, quality and community composition are necessary to predict likely outcomes of future changes in population densities of both species.     

REPRODUCTION BY NORTHERN BOBWHITES IN WESTERN OKLAHOMA

Abstract: We studied northern bobwhites (Colinus virginianus) in western Oklahoma, USA, during the nesting seasons of 1992–2001. We obtained latitude-specific information on nesting biology and tested hypotheses on the cause of declines in clutch size with progression of the nesting season and on the phenological relation of first, second, and third nesting attempts. For pooled data on bobwhites alive during 15 April-15 September, 64 ± 6.5% of juvenile females (n = 56), 90 ± 10.0% of adult females (n = 9), 13 ± 4.1% of juveniles males (n = 68), and 41 ± 10.7% of adult males (n = 22) incubated ≥ 1 nest. Bobwhites that entered the reproduction period starting on 15 April (n = 229) accumulated 203 nesting attempts (male and female incubations), which translated to 1.7 attempts/hen for all hens that entered (n = 117) and 3.1 attempts/hen for hens that survived to 15 September (n = 65). Overall success for incubated nests (48 ± 2.8%, n = 331) was independent of sex-age class and nesting attempt (1, 2, 3), but it declined at a rate of 2.37%/year (95% CL = 1.10–3.64%/year) during the study. Clutch size declined by 1 egg for every 14–20 elapsed days in the nesting season and the rate of decline was independent of incubation attempt (1 or 2); this result suggests that lower clutch sizes later in the nest season were not necessarily a function of re-nesting. Ending of nest-incubation attempts (1, 2, 3) occurred within an 8-day period from 26 August-2 September. Our results implied that early-season nesting cover is a management concern and that high nest success is possible in the absence of nest predator suppression where abundant nest sites occur across the landscape.     

9. LIST OF MEMBERS (as at date of publication)

We studied the breeding ecology of the Chestnut-backed Sparrowlark Eremopterix leucotis over three years between 2008 and 2010. The breeding season was bimodal with a main peak in laying in autumn (March–April) and another smaller peak in spring (September–October). Nest microhabitat analyses showed they prefer nesting in open areas with lots of bare ground (median 67.5%). Nest entrance directions were biased towards the south (mean vector (µ) = 186.44°). The majority of nests (78.2%) had an apron at the nest entrance. The mean clutch size was 1.88 but there was geographic variation in clutch size between northern and southern races of the species. The mean incubation and nestling periods were 10.33 d (range 10–11 d) and 9.20 d (range 8–10 d), respectively. The results suggest that parental contributions during incubation are almost equal, but females made significantly more food deliveries during the nestling period compared to males. The diet of nestlings comprised mainly of invertebrates (50.2%), seeds (34.4%) and unidentified food items (15.4%). Breeding success was low, averaging 16.1% (range 8.1–20.6%), and the average number of fledged young per pair was 0.36 ± 0.71. Replacement broods were common and we also recorded repeat brooding attempts.     

Issue Information

The population of Yellow‐naped Amazons (Amazona auropalliata) declined by an estimated 50% between 1980 and 2000, and the current population is estimated to be between 10,000 and 50,000. Poaching of young has been a persistent problem, but the species is also threatened by habitat loss and degradation. Because most aspects of their life history, behavior, and ecology have not been examined in wild populations, we studied Yellow‐naped Amazons with the following objectives: (1) identify the species of trees used for nesting, (2) determine the size and potential function of breeding territories, (3) determine nesting success, and (4) examine their duetting behavior. We located nests at 16 sites on the Pacific Slope of Costa Rica from 1999 to 2008. We searched for nests from January to May. Every nest was visited at least once and some nests were visited every 2–3 weeks throughout the breeding season. We also collected territory and duetting data at one site (Ahogados). The breeding season of Yellow‐naped Amazons was during the dry season (January–May). Yellow‐naped Amazons nested in 21 species of trees, but 68% of nests were located in only five species, and cavities in dead coyols (Acrocomia aculeata) were used most often. We found no association between breeding success and the species of tree in which birds nested. Mean territory size was 25,578 m², and these small areas generally consisted of several trees surrounding a nest tree. Pairs continued to duet throughout the breeding season, suggesting that duetting is important for territory defense. The nest failure rate in our study was 89%, and most nest failures (64%) were due to poaching for the pet trade. We recommend immediate population management and conservation actions, including increased law enforcement to reduce nest poaching, protection of key nesting areas, educational programs, and habitat conservation.     

Nesting biology and food habits of the endangered Sakalava Rail Amaurornis olivieri in the Mandrozo Protected Area,western Madagascar§

We studied the nesting biology and food habits of the endangered and endemic Sakalava Rail Amaurornis olivieri from July to November 2015 in the Mandrozo Protected Area, western Madagascar. Three nesting pairs were observed and their nests were constructed in a dense mat of reeds Phragmites mauritianus and averaged 56.7 ± 15.3 cm above the water (n = 3 nests). Nests were built by both adults and it took 3 d on average to complete a nest (n = 2 nests). Thirteen matings were observed and lasted 4.1 s on average (n = 2 pairs). Average clutch size was three eggs (n = 2 nests). Both sexes incubated; the incubation period was 15–17 d (n = 2 nests). Both male and female participated in brooding and feeding the young, which remained for 3 d in the nest and became independent of their parents at 45 d of age. Based on 194 identified food items, the Sakalava Rail’s diet was composed of invertebrates: spiders (53.1%), insects (32%), crustaceans (10.8%) and molluscs (4.1%). The home ranges of two radio-tagged individuals were 0.95 and 1.98 ha.     

Interspecific dominance and asymmetric competition with respect to nesting habitats between two snowfinch species in a high-altitude extreme environment

Interference competition over shared resources is expected to be intensive in harsh environments between phylogenetically and morphologically similar species. We document interspecific dominance and nest habitat selection by two pika-burrow nesting Montifringilla species, white-rumped snowfinches M. taczanowskii (WRS), and rufous-necked snowfinches M. ruficollis (RNS), which commonly inhabit alpine meadows in the northeastern Tibetan plateau. Relative to the critical point (<0.60) for coexistence, high overlaps (0.68–0.86) between the two species in egg-laying date, nest site distribution and nesting burrow attributes suggested strong interspecific competition over these niches. This is also predicted by the ratios of inter-species body mass (1.4) and linear dimensions (1.1–1.2) below the minimum value (2.0 and 1.3) for stable coexistence of closely related species. Larger-sized WRS was behaviorally dominant over pikas and over small-sized RNS. Being dominant, WRS established nesting territories in areas with moderately steep slopes from which they required most of the food resources during the breeding season; in contrast, RNS exhibited no territoriality and had to nest at margins between WRS’s territories and fed at dispersed sites. For the same reason, WRS mainly used active, and RNS used inactive, pika burrows. The asymmetric competition over nesting habitats could contribute to the relatively high nesting success and breeding density of the superior species. We argue that there is a spectrum in interspecific competition strength, from stable coexistence to complete exclusion along a gradient of increased environmental harshness, and the guild of the two snowfinch species is at a mediate position of the spectrum.     

Long‐term relationship between diet breadth and breeding success in a declining population of Egyptian Vultures Neophron percnopterus

Between 2000 and 2009 we studied the diet and breeding success of Egyptian Vultures Neophron percnopterus in southern Spain. Wild species accounted for 74.9% of prey items (n = 1071) with a predominance of mammals (62.3%), followed by birds (20.8%) and reptiles (13.1%). Spatially, the diet was highly varied and not restricted to carcasses of livestock; wild Rabbits Oryctolagus cuniculus accounted for 54% of the overall remains. The spatial variability may reflect regional and local disparity in the availability of main prey. The temporal relationship between variation in trophic diversity and Vulture nesting productivity (both values showing a long‐term decrease) might suggest a causal link between variation in diet and reproductive output. We hypothesize that high turnover rates could explain productivity variation as a consequence of the recruitment of less experienced individuals to the breeding population. This could in turn generate covariation between diet and reproductive output.     

Timing of breeding, habitat preference and reproductive success of marsh harriers (Circus aeruginosus)

During 2002–2005 we analyzed Lack’s Hypothesis about the timing of the breeding of marsh harriers (Circus aeruginosus) in the Poodří to the breeding period and preference of heterogeneous habitat. An analysis of 43 nests revealed quantitative differences. Birds which started breeding earlier, reached significantly higher reproductive success than later breeding birds regardless of nesting habitat (P = 0.003, n _nests = 43). Even when the birds invested into their offspring the same way, their breeding success was not always the same. When the females nested in the common reed (Phragmites communis), they reached higher reproductive output than females nesting in cattail (Typha sp.) (P = 0.01, n _cattail = 18, n _{common reed} = 25). The habitat of the common reed is characterized by higher and denser vegetation cover than cattail vegetation (P < 0.001, n _measurements = 174 for both variables).     

Feeding and hoarding behaviour of the Eurasian red squirrelSciurus vulgaris during autumn in Hokkaido, Japan

The feeding habits and hoarding behaviour of the Eurasian red squirrelSciurus vulgaris Linnaeus, 1758 were examined during autumn in Nopporo Forest Park (43°20’N, 141°30’E), in western Hokkaido, Japan. The diet consisted of 32 plant species. Twelve species were both eaten and hoarded (the two most common of which wereAbies sachalinensis andPinus koraiensis), and 20 species were eaten but not hoarded. The distance from where a food item was found to the hoarding spot averaged 50 m and differed significantly according to food type. WalnutsJuglans regia were transported farthest, and chestnutsCastanea crenata to the second farthest from the site of origin. Most food was hoarded beneath the ground surface (95%), but some were hoarded in forks of trees and in small tree holes. Squirrels selected food items of high energy content for hoarding, in preparation for winter and the breeding season.