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Likely Changes (likely + change)
Selected AbstractsGastrointestinal parasites of Howler monkeys (Alouatta palliata) inhabiting the fragmented landscape of the Santa Marta mountain range, Veracruz, MexicoAMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2010Carolina Valdespino Abstract In recent years populations of howler monkeys (Alouatta palliata) in southeastern Mexico have decreased substantially due to the transformation and loss of natural habitats. This is especially evident in the Santa Marta mountain range, Veracruz, Mexico where several studies have evaluated the impact of fragmentation on howler monkey populations in order to propose management programs for their conservation. The conditions generated by fragmentation likely change the rates of parasitic infection and could decrease howler survival. In this study, gastrointestinal parasite species richness, prevalence, and egg density of infection were determined in howler groups inhabiting five forest fragments at the Santa Marta mountain range. Two hundred and seventy-eight fresh fecal samples were collected between October 2002 and April 2003. Three parasite species were found during the dry and the wet season in all forest fragments sampled: one unidentified species of Eimeriidae; Trypanoxyuris minutus (Oxyuridae); and Controrchis biliophilus (Dicrocoeliidae). Both the prevalence of T. minutus and infection density for all parasites differed between seasons and fragments (the largest fragment consistently differed from other fragments). Host density, distance to the nearest town, fragment size, fragment shape, and total basal area of food trees explained parasite prevalence, but each species had a different pattern. Although parasite richness was lower, prevalence and density were higher than values reported for howlers in conserved forests. These results suggest that the establishment of biological corridors and animal translocation programs must take into account the parasite ecology of each fragment to avoid higher infection rates and preclude potential consequent mortality. Am. J. Primatol. 72:539,548, 2010. © 2010 Wiley-Liss, Inc. [source] Structural dynamics and robustness of food websECOLOGY LETTERS, Issue 7 2010Phillip P. A. Staniczenko Ecology Letters (2010) 13: 891,899 Abstract Food web structure plays an important role when determining robustness to cascading secondary extinctions. However, existing food web models do not take into account likely changes in trophic interactions (,rewiring') following species loss. We investigated structural dynamics in 12 empirically documented food webs by simulating primary species loss using three realistic removal criteria, and measured robustness in terms of subsequent secondary extinctions. In our model, novel trophic interactions can be established between predators and food items not previously consumed following the loss of competing predator species. By considering the increase in robustness conferred through rewiring, we identify a new category of species , overlap species , which promote robustness as shown by comparing simulations incorporating structural dynamics to those with static topologies. The fraction of overlap species in a food web is highly correlated with this increase in robustness; whereas species richness and connectance are uncorrelated with increased robustness. Our findings underline the importance of compensatory mechanisms that may buffer ecosystems against environmental change, and highlight the likely role of particular species that are expected to facilitate this buffering. [source] THE COMPETITION COMMISSION INQUIRY INTO SME BANKINGECONOMIC AFFAIRS, Issue 4 2002Peter Freeman This article describes the current Fair Trading Act régime for complex monopoly investigations with particular reference to the Competition Commission's recent SME Banking Inquiry. There then follows a critique of aspects of the process and an outline of the market investigation régime in the proposed Enterprise Act with an assessment of likely changes this will make to investigations of this kind. [source] Fish community characteristics of the lower Gambia River floodplains: a study in the last major undisturbed West African riverFRESHWATER BIOLOGY, Issue 2 2009VASILIS LOUCA Summary 1.,The Gambia River is the last major West African river that has not been impounded. However, a hydroelectric dam is being constructed and substantial changes to the hydrology and ecology of the system are expected. 2.,Little information is available on the impact of water impoundments in semi-arid regions on downstream floodplain fish communities, due to the scarcity of pre-intervention data. Because profound impacts on physical habitat, salinity and nutrient transport can occur downstream of such impoundments, a knowledge of the species-habitat associations of biota such as fishes is necessary for understanding likely changes and how to limit them. 3.,Fish were sampled using cast and hand nets along two transects on the floodplain, and with fyke nets in two ,bolongs' (creeks) from May to November 2005 and 2006 in the lower reaches of the Gambia River, close to the salt water front where ecological changes due to the construction of the dam are likely to be pronounced. 4.,Greatest fish species richness was associated with low conductivity, low pH and deep water. Bolongs held greater species richness compared with other floodplain habitats, probably because they acted as conduits for fish moving on and off the floodplain. Species richness and catch biomass increased rapidly following the first rains and then declined. 5.,Using a multivariate analysis, three main species groups were identified on the floodplain; one associated with deeper water, one with less brackish water and one with shallow, open water. Tilapia guineensis was the commonest species on the floodplains. 6.,The floodplains provide nursery habitats as many fish captured were immature, particularly for species where adults are mainly encountered in the main channel. Several small-sized floodplain specialists were also represented by a high proportion of mature individuals. 7.,Impoundment is expected to reduce seasonal flooding of the floodplain in the lower Gambia River, downstream of the impoundment, resulting in reduced occurrence of aquatic habitats, especially bolongs, together with lower dissolved oxygen and increased salinity, leading to alteration of the floodplain fish communities, benefiting salt-tolerant species, reducing overall species richness and probably reducing floodplain fish production. [source] Regional and local labour market prospects: the importance of ageing in workforce developmentPOPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 5 2006Anne Green Abstract Overall, the labour force in the UK is ageing, although at different rates in different areas. This poses challenges for workforce development, and has implications not only for older workers, but for everyone, everywhere. However, demography is only one element in labour supply. It needs to be considered alongside trends in participation rates and in a broader policy and cultural context, and alongside likely changes in labour demand, in order to gain a picture of regional and local labour market prospects. The thrust of government policy is to raise employment rates amongst older people (aged 50,69) and to promote ,active ageing'. The decline in employment rates amongst older men evident in the 1980s has been reversed, but participation rates remain low by earlier standards. Shifts in the industrial and occupational structure of employment mean that there is likely to be a growing demand for customer care and service skills, which older people are well-placed to provide. Yet estimates of ,replacement demand' show that some of the most pressing workforce development issues are experienced in declining sectors and occupations, with an older than average age profile. Examples include agriculture and social care in Cornwall, where there is a lack of new recruits to replace those retiring. It is concluded that improved local intelligence on labour market flows and prospects is needed to inform skills and learning priorities. Copyright © 2006 John Wiley & Sons, Ltd. [source] | ||||||||||