Habitat preferences of the Andean bear (Tremarctos ornatus) in the Bolivian Andes

Habitat preferences of the Andean bear Tremarctos ornatus were studied within two adjacent protected areas in the north-western Bolivian Andes. Standard transects measuring habitat variables and bear sign frequency were used spanning seven different vegetation types. Andean bears were present at 28 of 33 sampled sites and actively preferred high-elevation elfin forest and upper montane humid forests, and used high-elevation humid 'páramo' grasslands and middle montane humid forests according to their availability. Bears were absent from dry montane and Andean foothill forests and relative abundance was low in lower montane humid forests. Elevation and basal area of food items were the variables most closely related to the relative abundance.     

Starting from scratch: A first look at a “displacement activity” in group-living rhesus monkeys

Data on scratching behavior were collected from a group of rhesus monkeys living in spacious surroundings. Juveniles scratched more often than adults. Adults scratched most often in social contexts and in close temporal association with a change of behavior. Subjects of intermediate dominance rank, in particular, scratched around the time of a behavioral change, and these subjects were the only ones to show increased scratching during tests involving restricted access to food (thwarting or frustration). The outer thighs, lower back, and sides were the sites scratched most frequently, not necessarily matching sites reported to be preferred for self-grooming. Scratching in monkeys has certain characteristics in common with some well-studied displacement activities in other species, and it possibly also serves as a signal that the individual is preparing to change behavior.     

Habitat use and diversity of waterbirds in a coastal lagoon around Lake Biwa, Japan

We investigated habitat use and diversity of waterbirds at one of the coastal and satellite lagoons around Lake Biwa, which is a registered wetland of the Ramsar Convention in Japan. To evaluate the importance for waterbirds of a lagoon around the freshwater lake, we conducted 26 censuses over 1 year on seven blocks with different landscape elements in a small lagoon. A total of 25 species were found and most of them (72%) belonged to a guild in which birds forage without diving. Species density (per ha) and diversity was high in blocks where Zizania latifolia Turcz and Phragmites australis L. reed beds existed. Not all of the waterbird species were feeding all the time, but were often resting in their preferred blocks, suggesting that they use the lagoon as both a refuge and a feeding site. Habitats with a structural reed bed community and shallow waters (<1 m depth) may be crucial determinants of high waterbird diversity in this small lagoon around which many people live.     

异地半圈养藏羚卧息行为适应性的初步研究

藏羚Pantholops hodgsoni是青藏高原特有物种。为了探讨藏羚羊对异地环境的行为学适应,对异地圈养藏羚羊的卧息行为进行了不同性别、不同季节间的比较研究。采用全事件记录法和焦点动物取样法,记录和统计了异地圈养藏羚羊冷季和暖季的卧息行为。研究结果表明,在暖季,雌性和雄性藏羚羊在卧息时间及卧息时间占全天活动时间的比例(卧息比例)上没有差异(卧息时间:Z=-1.126,P0.05;卧息比例:Z=-1.357,P0.05);在冷季,雌性和雄性藏羚羊在卧息时间及卧息比例上也没有差异(卧息时间:Z=-1.14,P0.05;卧息比例:Z=-0.307,P0.05)。雄、雌性藏羚羊的卧息时间及卧息比例没有季节差异(雄性卧息时间:Z=-1.465,P0.05;雄性卧息比例:Z=-1.631,P0.05;雌性卧息时间:Z=-1.742,P0.05;雌性卧息比例:Z=-1.852,P0.05)。季节和性别对藏羚羊卧息行为的影响没有交互作用(F=0.057,P0.05)。总之,藏羚羊卧息行为之间既没有性别差异也没有季节差异,与可可西里地区藏羚羊的卧息行为相比,异地圈养藏羚羊的卧息行为已经调整其行为学适应对策。     

锦绣龙虾人工繁殖和胚胎发育的研究

锦绣龙虾(Panulirus ornatus)是世界名贵的经济虾类, 也是我国捕捞和养殖的大型虾类, 但资源匮乏,育苗还没有取得成功, 因此, 需要开展人工繁殖研究以保护和增殖资源。实验用人工养殖26 月龄的锦绣龙虾进行人工繁殖和胚胎发育研究, 结果表明, 锦绣龙虾在5 个月内繁殖2 次。切除锦绣龙虾单侧眼柄能加速其性腺发育, 在第一和第二次繁殖中, 切除眼柄的雌龙虾比对照组的卵巢成熟时间分别缩短17.7d 和11.3d。锦绣龙虾在交配后1—10d 内产卵。锦绣龙虾切除眼柄与否对怀卵量没有显著影响。第一、二次繁殖平均产卵量分别为40.34×104 粒和32.97×104 粒, 平均孵化率分别为77.29%和77.72%, 孵化出叶状幼体平均数量分别为31.38×104/尾和25.62×104/尾。锦绣龙虾的胚胎发育分为11 个时期: 受精卵、卵裂期、囊胚期、原肠期、膜内无节幼体期、七对附肢期、九对附肢期、十一对附肢期、复眼色素形成期、准备孵化期和孵化期。在水温29.2℃, 盐度30, 受精卵经22—23d 孵化出叶状幼体。     

Hazel grouse (Bonasa bonasia) pairs during the nonbreeding season: mutual benefits of a cooperative alliance

During the nonbreeding season (autumn and winter), hazel grouse(Bonasa bonasia) males and females associate as loosely boundpairs, not as strongly bound pairs as previously thought. Thesepairs could be considered cooperative alliances, with each membergaining both direct and indirect benefits. The most importantdirect benefit appeared to be mutual vigilance against predators.This benefit was found at two levels: at the level of arborealfeeding sites, two birds could forage faster and farther fromcover than single birds, and at the territory scale, the pairwas together more in dangerous habitats. By foraging fartherfrom cover, two birds could use about 23% more of the preferredfood trees and 9%–10% more of the food available withina territory than a single bird, partially mitigating the costof having two birds feeding on limited winter food in the samespace. Defending a common territory appeared to be a less importantdirect benefit of the alliance because the members of a pairdid not defend the same territory and often associated withneighboring birds of the opposite sex. A future benefit of thealliance was having breeding partners in the spring; this wasmost beneficial for males, as the sex ratio was male biased.Members of the pair were often apart. At arboreal feeding sites,this separation was perhaps because the most preferred trees,black alders (Alnns glutinosa) with the most staminate catkins,were located in areas with the most cover, where one bird maybe safer from predators than two. Members of pairs in more securehabitats were more often with extrapair birds of the oppositesex. This suggested a trade-off; birds in safe habitats mayhave visited potential breeding partners, but birds in dangeroushabitats may have had to remain together, foregoing this option,to increase their survival probability. This social organizationappeared to be an adaptation to surviving in a heterogeneoushabitat, with some of the winter food located in dense coverand some located in more open and dangerous situations.     

Social responding to mirrors in rhesus macaques (Macaca mulatta): Effects of changing mirror location

Two rhesus macaques (Macaca mulatta) with a lifetime of continuous exposure to mirrors showed a dramatic and reliable reinstatement of social behavior directed toward the mirror when it was simply moved to a new location. These data are discussed in the context of repeated failures to find self-recognition in monkeys and several recent claims that a cessation of social behavior directed toward mirrors can be used as evidence for the beginning of self-recognition in nonhuman primates.     

Social Contact Following Severe Aggression in Rhesus Macaques (Macaca mulatta): A New Test of the Consolation Hypothesis

Previous studies on macaque species revealed no evidence of consolation: affiliative contact between the loser of an aggressive interaction and a third party. However, typically, the researchers used short observation periods and latency to make first affiliative contact as a dependent measure. Based on social stress buffering literature, I predicted that by employing longer observation periods and percentage of time in affiliative contact as a dependent measure, I would be more likely to detect increases in affiliative contact following aggression. I observed adult female rhesus macaques for 1 hr after they received severe aggression and for 1 hr after some affiliative contact, and measured time spent in affiliative contact using instantaneous recording at 30-sec intervals. Contrary to prediction, victims of attack did not spend a greater percentage of time in affiliative contact postaggression as compared to postaffiliation. Subjects were also less likely to initiate contact with other individuals and were more likely to have contact with individuals that were dominant to their aggressor, following aggression. These results provide converging evidence that affiliative contact is not increased following aggression in macaques. I discuss the failure to bear out the predictions based on the social stress buffering literature in terms of rhesus social dynamics, the nature of aggression as a stressor, and possible mechanisms for the social stress buffering effect.     

Testing hypotheses of social gatherings of common loons (<Emphasis Type="Italic">Gavia immer</Emphasis>)

Three hypotheses are tested to explain the function of common loon social gatherings: Cooperative Foraging, Familiarity, and Reconnaissance. From 1993 to 1999, I studied social gatherings through behavioral observations in Michigan, Wisconsin and Maine. There was no or little evidence for the Cooperative Foraging Hypothesis. Partial or indirect evidence for the Familiarity Hypothesis included the following: (1) Social gatherings lasted both longer and occurred more frequently later in the breeding season (2) Approximately 25% of all the social gatherings observed occurred on neutral territories, and (3) Social gatherings consisted of the same individuals on consecutive days. Predictions from the Reconnaissance Hypothesis were also supported in that a large proportion of individuals participating in social gatherings were non-breeders and that the number of social gatherings observed were not equally distributed across loon territories, but instead increased on territories that had recently undergone a divorce. No one hypothesis was adequate to explain social gatherings and more observations on uniquely marked individuals are needed to further substantiate these initial findings.