Fecal corticosterone, body mass, and caching rates of Carolina chickadees (Poecile carolinensis) from disturbed and undisturbed sites

We tested for hormonal and behavioral differences between Carolina chickadees (Poecile carolinensis) taken from a disturbed (recently logged) forest, an undisturbed forest, or a residential site. We measured fecal corticosterone and body mass levels in the field, and fecal corticosterone, body mass, and caching behavior in an aviary experiment. In the field, birds from the disturbed forest exhibited significantly higher fecal corticosterone levels than birds from either the undisturbed forest or from the residential site. Birds from the disturbed forest also exhibited lower body mass than those from the undisturbed forest but higher body mass than those from the residential site. Our aviary results suggest that these physiological differences between field sites are the result of short-term responses to ecological factors: neither body mass nor fecal corticosterone levels varied between birds captured at different sites. Aviary sample sizes were sufficient to detect seasonal variation in fecal corticosterone (lowest in summer), body mass (highest in spring), and rate of gain in body mass (highest in winter). Under "closed-economy" aviary conditions (all food available from a feeder in the aviary), there were no site differences in the percent of seeds taken from the feeder that were cached. However, under "open-economy" conditions (food occasionally available ad libitum), significantly fewer seeds were cached by birds from the disturbed forest compared to the undisturbed or residential sites. On average, there was only a two-fold difference in population levels of fecal corticosterone. This difference is about the same as an increase in fecal corticosterone induced by a 2-h increase in food deprivation and cannot be considered to be an acute stress response to disturbance.     

A functional relationship between species richness of spiders and lichens in spruce

Modern forestry has created stands with even age distribution of trees and fragmentation of the habitat. In boreal forests, the effects on biodiversity within many taxa need to be examined. We tested the hypothesis that species richness of foliose and fruticose lichens and spiders is positively related in the lower canopy of spruce (Picea abies) in forests with, or without, management in central Sweden. High species richness of lichens may increase the structural complexity of the microhabitat on spruce branches, and bring a higher species richness also in the spider community. In six areas, spruce branches were sampled in old-growth and managed boreal forest stands, respectively. Forest management did not affect the species richness of spiders or lichens, but an effect due to sampling area was found in the latter taxon. There was a significant covariation between species richness of lichens and spiders, and the hypothesised positive correlation was confirmed by separate analyses for each area and combining the probabilities. Moreover, regression analysis on mean values from each site revealed a positive relationship. We conclude that species richness of lichens and spiders covary on spruce branches for functional reasons, i.e. more lichen species promotes a more diverse spider community by increasing the structural heterogeneity. Our results might provide a shortcut for assessing biodiversity in boreal forests.     

Selective felling as a potential tool for maintaining biodiversity in managed forests

In Sweden one forestry method, the clear-cutting method, has been used all over the country despite differences in climate, topography etc. At present there is a growing interest in using alternative methods such as selective felling, which to a larger extent mimic natural disturbances. In this study we compare virgin forests with stands which have been cut with old selective felling (dimension felling), new selective felling (single tree selection felling), and clear-cutting with respect to frequency of characters important to biodiversity (mainly dead wood). The frequency of different types of dead wood decreases with increasing intensity of the cutting method in the following order: old selective felling, new selective felling, and clear-cutting. New selective felling had higher amounts and quality of dead wood compared to clear-cutting. New selective felling also showed less differences compared to virgin forests than clear-cutting. Dead wood in new selective felling compared to clear-cutting may offer substrate for different types of faunas because of the environment surrounding the dead wood. Even if the new selective felling method seems to provide higher amounts of dead wood compared to the clear-cutting method, further studies of organisms utilising the dead wood are needed. New selective felling does not seem to solve the problem of decreasing availability of dead wood in managed forests and there is still a need to preserve unmanaged forest patches in a landscape perspective in order to offer habitats with a high amount of dead wood.     

Indian Science for Indian Tigers?: Conservation Biology and the Question of Cultural Values

The implementation of Project Tiger in India, 1973–1974, was justly hailed as a triumph of international environmental advocacy. It occurred as a growing number of conservation-oriented biologists were beginning to argue forcefully for scientifically managed conservation of species and ecosystems – the same scientists who would, by the mid-1980s, call themselves conservation biologists. Although India accepted international funds to implement Project Tiger, it strictly limited research posts to Government of India Foresters, against the protests of Indian and US biologists who hoped to conduct the scientific studies that would lead to better management and thus more effective conservation of the tiger. The foresters were not trained to conduct research, and in fact did not produce any of significance for the first 15 years of Project Tiger’s existence. The failure of biologists to gain access to India’s tigers in the 1970s was caused by many factors, but not least among them was a history of disdain among conservation-oriented biologists for government officials managing reserves, and the local politics of conservation. Project Tiger, then, serves as a case study for the discussion of the intersection of conservation biology with non-scientific concerns, including nationalism and the desire of the Indian government to more completely control its land.¹I would like to thank the participants in the 2003 Southwest Colloquium for the Life Sciences for their constructive comments on an earlier version of this paper, as well as the two unusually helpful (anonymous) reviewers.     

Short-term effects of experimental boreal forest &;logging disturbance on bumble bees,bumble &;bee-pollinated flowers and the bee–flower match

This study examines how, over the short term, logging affects the density of bumble bees (Apidae: Bombus), the understory plants commonly visited by bumble bees, and the numerical relationship between bumble bees and flowers. In the summers before and after winter logging, bumble bees and plants were surveyed in 50 deciduous stands (each of 8–10 ha) in the boreal forest of northern Alberta, Canada. Logging was replicated at three different intensities: 0, 10–20, and 50–75% of trees remaining. There were generally more bumble bees, species of bumble bee-visited plants, and flowers in moderately (50–75%) logged sites, but this pattern depended on the time of year. Before logging, bumble bees matched resources according to an ideal free distribution (IFD). Logging affected the distribution of bumble bees across floral resources: the slope of the regression relating bumble bee and flower proportions was less than one for clearcut and control treatments (i.e., undermatching), with too many bumble bees in the flower-poor compartments and too few in the flower-rich ones. Deviations from an IFD were negative in control sites, such that fewer bumble bees occurred here than warranted by flower numbers. Controlling for flower density, bumble bee density was significantly greater in clearcuts than in the other treatments. By disproportionately visiting plants in clearcuts (relative to flower density), and by undermatching, bumble bees in clearcuts should experience higher levels of competition. Conversely, the fewer (and undermatching) bumble bees in control sites (relative to flower abundances there) may cause these plants to obtain diminished pollination service. The proximity of clearcut logging to pristine areas may therefore negatively impact plants and bumble bees in the pristine areas, at least in the season immediately following logging.     

Distribution, habitat characteristics and conservation requirements of a forest-dependent threatened invertebrate Lissotes latidens (Coleoptera: Lucanidae)

The distribution, habitat and conservation requirements of an endangered stag beetle, Lissotes latidens (Coleoptera: Lucanidae), in south-east Tasmania were investigated. This study trebled the known range of the species to 280 km², of which 15% constituted potential habitat. The beetle was found to inhabit a range of wet forest types including damp eucalypt forest, wet eucalypt forest, rainforest and riparian areas amongst drier forest types. Relative to other Tasmanian lucanids, L. latidens was found to occur at quite low population densities. The species had a preference for forest with a well-developed overstorey and greater than 10% ground cover of coarse woody debris (CWD). Although L. latidens is soil-dwelling throughout its life-cycle, it has a close association with CWD, occurring under logs at the interface of soil and CWD. Suitable forest habitat for L. latidens is poorly reserved, with 48% managed under clearfell, burn and sow forestry regimes; a practice that is likely to lead to the depletion of CWD over successive harvesting rotations. Recommendations are made for the conservation management of habitat utilised by L. latidens in off-reserve areas. The need for conservation strategies to incorporate the temporal dynamics of habitat important to forest-dependent threatened species is discussed.     

Gender Equity in Social Forestry Programs in Bangladesh

Conceptual issues of gender equity in development are examined and analyzed with respect to the Social forestry project (Village and Farm Forestry Project; VFFP) as a means to redistribute access to productive resources and household benefits. A random sample of 120 VFFP participants, both men and women, was interviewed regarding their division of labor and their access to resources and benefits in relation to the project. The survey suggests that women and men produce different quantities and types of labor for the VFFP. Although women supply more labor than men, it is possible that women's overall labor burden is reduced in relation to the national average. For VFFP participants called core farmers, women enjoy the same access to productive resources and services as men, with the important exception that women do not generally have land rights. Yet 100% of interviewed women core farmers answered positively to six indicators of sociocultural advancement because of their participation in the VFFP. Among a second tier of VFFP participants called participating farmers, a large majority of women respondents claim rights on most resources and services important in the VFFP, although these proportions are less than among men respondents. Most women participating farmers answered affirmatively to the six indicators of sociocultural advancement, but in lesser proportions than among women core farmers.     

滩地林业生态工程与钉螺孳生关系的研究

研究表明,草滩钉螺密度与淹水时间呈正相关,淹水时间与林木生长性能呈负相关．淹水期每增加１天,钉螺密度上升２２６９个·ｈｍ－２．滩地实施抑螺林业生态工程３年后钉螺密度下降８４％．     

广东林业可持续发展问题探讨

面对广东林业新的发展机遇,以最新的资源数据,从科学发展观的角度,通过对广东林业建设现状的分析,指出了广东林业目前迫切需要解决的问题,探讨了在新形势下适合广东实际的林业可持续发展道路,进而对贯彻“以人为本,生态优先”、发展以生态建设为主的现代林业,实现广东林业的可持续发展提出了策略性的建议。     

Détermination des sites d'oxydation des dérivés du α-D-glucofuranose utilisés comme donneurs

The sites of oxidation, by catalytic transfer of H, of derivatives of 1,2-O-isopropylidene-α-D-glucofuranose suggest a regiospecific reaction. Compounds having vicinal hydroxyl groups at C-5 and C-6, or at C-3 and C-5, are oxidized at OH-5, whereas compounds having two hydroxyl groups at C-3 and C-6 or three hydroxyl groups give first aldehydes and then lactones.