Population census of the white-headed langur (Trachypithecus leucocephalus) at Longrui Karst Hills, Guangxi, China

A population census of white-headed langurs (Trachypithecus leucocephalus) was conducted using sleeping-site counts and the line-transect method from July to August 2002 at the Longrui Karst Hills, Guangxi, China. This area had been the largest habitat of the langurs across their range before the 1990s. While our survey revealed 146 old sleeping-sites, no white-headed langurs or fresh sleeping-sites were found in this area. Our study indicated that there had previously been a large population of langurs at Longrui Karst Hills, but now the langurs are possibly locally extinct in this area. If langurs still exist within the area, the population density must be very low. Interviews with local people confirmed that the number of white-headed langurs has been decreasing since the 1980s. Poaching was very common in the past and continues to be a problem at present, and it is likely that this has caused the decrease in the white-headed langur population at Longrui Karst Hills.     

Intestinal cell kinase (ICK) promotes activation of mTOR complex 1 (mTORC1) through phosphorylation of Raptor Thr-908

Intestinal cell kinase (ICK), named after its cloning origin, the intestine, is actually a ubiquitously expressed and highly conserved serine/threonine protein kinase. Recently we reported that ICK supports cell proliferation and G(1) cell cycle progression. ICK deficiency significantly disrupted the mammalian target of rapamycin (mTOR) complex 1 (mTORC1) signaling events. However, the biological substrates that mediate the downstream signaling effects of ICK in proliferation and the molecular mechanisms by which ICK interacts with mTORC1 are not well defined. Our prior studies also provided biochemical evidence that ICK interacts with the mTOR/Raptor complex in cells and phosphorylates Raptor in vitro. In this report, we investigated whether and how ICK targets Raptor to regulate the activity of mTORC1. Using the ICK substrate consensus sequence [R-P-X-S/T-P/A/T/S], we identified a putative phosphorylation site, RPGT908T, for ICK in human Raptor. By mass spectrometry and a phospho-specific antibody, we showed that Raptor Thr-908 is a novel in vivo phosphorylation site. ICK is able to phosphorylate Raptor Thr-908 both in vitro and in vivo and when Raptor exists in protein complexes with or without mTOR. Although expression of the Raptor T908A mutant did not affect the mTORC1 integrity, it markedly impaired the mTORC1 activation by insulin or by overexpression of the small GTP-binding protein RheB under nutrient starvation. Our findings demonstrate an important role for ICK in modulating the activity of mTORC1 through phosphorylation of Raptor Thr-908 and thus implicate a potential signaling mechanism by which ICK regulates cell proliferation and division.     

北京2种猛禽新分布记录

在2010年春季北京西郊迁徙猛禽调查中,我们记录到未见于历史文献(蔡其侃,1987;高武等,1991;赵欣如,1999;自然之友,2001)和已发表的北京鸟类新分布记录报道(张正旺等,2003;刘阳等,2005;朱雷等,2011)的2种猛禽:松雀鹰(Accipiter virgatus)和蛇雕(Spilornis cheela)。1松雀鹰(Accipiter virgatus)2010年4月4日上午,于北京百望山森林公园南端山顶处拍摄到一只低空飞过的中型鹰类(见封4:图1)。其脸颊青灰色,喉白而具明显的黑色喉中线,     

Mammalian Target of Rapamycin Complex 1 (mTORC1) and 2 (mTORC2) Control the Dendritic Arbor Morphology of Hippocampal Neurons

Dendrites are the main site of information input into neurons. Their development is a multistep process controlled by mammalian target of rapamycin (mTOR) among other proteins. mTOR is a serine/threonine protein kinase that forms two functionally distinct complexes in mammalian cells: mTORC1 and mTORC2. However, the one that contributes to mammalian neuron development remains unknown. This work used short hairpin RNA against Raptor and Rictor, unique components of mTORC1 and mTORC2, respectively, to dissect mTORC involvement in this process. We provide evidence that both mTOR complexes are crucial for the proper dendritic arbor morphology of hippocampal neurons. These two complexes are required for dendritic development both under basal conditions and upon the induction of mTOR-dependent dendritic growth. We also identified Akt as a downstream effector of mTORC2 needed for proper dendritic arbor morphology, the action of which required mTORC1 and p70S6K1.     

Legal protection of wolves in Poland: implications for the status of the wolf population

Legal protection of wolves (Canis lupus) in Poland was implemented in 1998 after 23 years of management as a game species. Wolves occurring in Poland were interconnected with larger populations in the Carpathian Mountains and Belarus, Baltic States and Russia, stable in numbers, and were not considered endangered before the change in legal status affording protection from hunting. Parties calling for wolf protection wanted to stop killing of wolves because of their symbolic nature, but did not have particular management goals to achieve. The government did not accompany the change in legal status by management plan, and therefore, the ban on wolf hunting was weakly enforced. A wolf distribution monitoring demonstrated that wolf range had not expanded 9 years after the hunting ban was implemented, and no increase in wolf numbers was observed. This failure to recover may be explained by: (1) a significant (up to 35%) reduction in the wolves’ prey base 6 years before wolf hunting was stopped, (2) weak enforcement of the protection law, resulting in lack of poaching control of wolves, (3) probable increasing fragmentation and isolation of wolf habitat caused by rapid economic growth in Poland. Inconsistent application of current management policy toward wolves resulted in weak enforcement of regulations and promoted negative attitudes toward the species. To improve the status of wolves in Poland, I recommend a flexible wolf management planning framework that involves and addresses attitudes of hunters and sheep herders, includes a framework to promote strong law enforcement, and consistent, fair compensation for livestock killed by wolves.     

Parental care of kestrels living in stable and varying environmental conditions

We studied parental behaviour of two populations of Eurasian kestrels (Falco tinnunculus) living in environments with different reproductive constraints: a northern Italy population, resident, with relatively long reproductive season and almost stable prey availability, and a western Finland population, long-distance migrant, with short reproductive season and fluctuating availability of main prey (voles). The Finnish population was studied during a low vole availability year. We aimed to test the supposition that in variable environments the few pairs capable of breeding during low prey availability years show high-quality parental care. To estimate the quality of parental care in both Finnish and Italian pairs we measured the difference in the number of prey delivered by the male and by the female within each pair. The parental care, measured by that parameter, was greater among Italian pairs during both the incubation and early nestling periods. However, this was not the case in the late nestling period, when food requirements of offspring are greater. Moreover, the Finnish and Italian pairs produced about the same number of fledglings. Therefore, our data supported the initial supposition and we conclude that the few Finnish pairs capable of breeding in a low vole availability year show parental care similar to Italian pairs.     

Wildlife crime promoted by weak governance

Wildlife crime such as illegal hunting of elephants and rhinos is currently one of the major issues in conservation. In order to combat poaching, law enforcement is essential. Here, we reviewed wildlife cases from the Northern Zone Anti‐Poaching Unit, Arusha, Tanzania (APU‐Arusha), focusing on the types of wildlife offence committed, prosecution outcomes and the sentences awarded to the offenders who were found guilty by the courts. Eighty‐two registered cases were thoroughly reviewed. The majority of wildlife offences committed were unlawful possession of, and failure to report, government trophies. It was found that only 16% of the accused were found guilty, 6% were acquitted, 30% of the charges were withdrawn, and 48% of the cases were discharged by the director of public prosecution (DPP) or magistrate. The poor conviction rate was attributed to weak evidence, failure of the prosecution to prove cases beyond reasonable doubt, lack of cooperation between the zonal game office and the DPP, and in some cases, the accused jumped their bails. Understanding the factors which allow individuals to continue to engage in poaching and the factors that promote the practice of good governance is vital in trying to stop wildlife crimes.     

Curved paths in raptor flight: Deterministic models

Two deterministic models for flight of Peregrine Falcons and possibly other raptors as they approach their prey are examined mathematically. Both models make two assumptions. The first, applicable to both models, is that the angle of sight between falcon and prey is constant, consistent with observations that the falcon keeps its head straight during flight and keeps on course by use of the deep foveal region in its eye which allows maximum acuity at an angle of sight of about 45 degrees . The second assumption for the first model (conical spiral), is that the initial direction of flight determines the overall path. For the second model (flight constrained to a tilted plane), a parameter that fixes the orientation of the plane is required. A variational calculation also shows that the tilted plane flight path is the shortest total path, and, consequently, the conical spiral is another shortest total path. Numerical calculations indicate that the flight paths for the two models are very similar for the experimental conditions under which observations have been made. However, the angles of flight and bank differ significantly. More observations are needed to investigate the applicability of the two models.     

Competitive interactions among raptors in boreal forests

We examined inter-specific interactions among goshawks (Accipiter gentilis), common buzzards (Buteo buteo) and honey buzzards (Pernis apivorus) in western Finland in 1983–1996. Because goshawks are among the largest birds of prey species in boreal forests they may take over the nest of smaller and less-competitive forest-dwelling raptors when searching for suitable places for breeding. Accordingly, more than half of newly established goshawk territories were found on the territories previously occupied by the common buzzard and the honey buzzard. Otherwise, territory sharing between these species was rare. Fledgling production of honey buzzards was not associated with the presence of goshawks, probably owing to the almost 2 months later onset of breeding. This probably decreases competitive interactions between these two species. An intensive interference competition, instead, seemed to be evident between common buzzards and goshawks, because the fledgling production of common buzzards was decreased by 20% as a result of failures during incubation and nestling period in the vicinity (<1 km) of occupied goshawk nests. Similarly, territory occupancy of common buzzards till the next breeding season was significantly reduced in the presence of goshawks. Relatively high proportions of occupied buzzard territories (17%) in the study area were shared by breeding goshawks on the same territory. This suggests that although their diets are dissimilar they inhabit similar habitats and might compete for the available prime nesting habitats within forest landscapes. In addition, goshawks benefit from taking over the complete nests of other raptors, imposing upon the original owners of the nest, because building a large stick nest is probably energetically costly. As a large raptor, the goshawk apparently has a competitive advantage over smaller ones, and may have an ever-increasing impact on smaller birds of prey, if there is a lack of sheltered forests inducing competition for the available nest sites.     

Factors promoting polygyny in European birds of prey—a hypothesis

Summary Polygyny is known in at least nine (out of 36) European raptor (Accipitriformes and Falconiformes) and seven (out of 13) owl (Strigiformes) species that hunt mobile prey. The hypothesis put forward here suggests that abundant food supply and nomadic tactics of breeding dispersal are crucial factors promoting polygyny in birds of prey. The hypothesis predicts that: (1) polygyny is more common in rodent-eating birds of prey than in bird-eating ones; (2) polygyny is more frequent in good vole years than in poor ones; (3) the frequency of polygyny in vole-eating species should increase northwards in Europe, as the densities of voles in the peak phase increase in that direction; (4) the frequency of polygyny and harem size should be increased by supplementary feeding; and (5) polygyny is more common in nomadic birds of prey with annual pair bonds and weak territoriality than in resident birds of prey with longerterm pair bonds and stronger territoriality. A majority of the available data is consistent with predictions 1–3 and 5, but data on prediction 4 are scanty. Further studies on ringed birds of prey are needed to test the validity of the hypothesis.