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North-east Scotland (north-east + scotland)
Selected AbstractsSocial and population structure of a gleaning bat, Plecotus auritusJOURNAL OF ZOOLOGY, Issue 1 2000A. C. Entwistle Abstract Brown long-eared bats Plecotus auritus occupying 30 summer roosts in north-east Scotland were studied over 15 years. During this time 1365 bats were ringed, and a further 720 recaptures were made. Individual bats showed a high degree of roost fidelity, returning to one main roost site; < 1% of recaptured bats had moved among roost sites, and all recorded movements (n= 5) were < 300 m. Adults of both sexes were loyal to the roost sites at which they were first captured, indicating long-term use of roosts. At least some juveniles (n= 32) of both sexes returned to the natal roost. Mark,recapture estimates indicated that colonies of this species were substantially larger (c. 30,50 individuals) than assumed in previous studies. Plecotus auritus differs from most other temperate zone, vespertilionid species in that there was no evidence of sexual segregation during summer, with males present in all colonies throughout the period of occupancy. Population structure in summer seems to be consistent with a metapopulation model, with discrete sub-populations showing minimal interchange. The group size, colony composition and population structure described in this species may be associated with the wing shape (particularly aspect ratio) and foraging behaviour of P. auritus. It is postulated that relative motility, linked to wing structure, may affect the distribution of individuals, and may have implications for the genetic structure of this species. Correlations between aspect ratio and both colony size and migratory behaviour, across British bat species, indicate that wing shape could be an important factor contributing to patterns of social behaviour and genetic structuring in bats. [source] Potential contribution of selected canopy traits to the tolerance of foliar disease by spring barleyPLANT PATHOLOGY, Issue 6 2009I. J. Bingham A model of canopy photosynthesis and above-ground growth rate was used to investigate the potential impact of several canopy traits on tolerance of foliar disease by barley. Disease tolerance was defined as the reduction in predicted crop dry-matter growth rate per unit of visible disease symptoms. The traits were canopy area (leaf area index, LAI), light extinction coefficient (k) and the ratio of virtual to visible lesion size (,). The effects of altering the area of the healthy flag leaf and its light-saturated rate of photosynthesis (Pmax) in response to disease elsewhere on the plant were also investigated. The model was parameterized for spring barley and run with a solar radiation and temperature regime typical of north-east Scotland. Predicted reductions in growth rate per unit increase in disease were greatest at high disease severity and when disease was distributed relatively uniformly through the canopy. Tolerance was increased by increasing LAI to >3 and k to >0·3, but the beneficial effects depended on the severity and, to a lesser extent, the distribution of disease. Tolerance was reduced by increasing ,. A sensitivity analysis performed at a single disease severity and distribution showed that tolerance was most sensitive to variations in , and compensatory adjustments in area and Pmax of the flag leaf, and least sensitive to whole canopy LAI and k. Future research should quantify the genetic variation in these traits within barley germplasm to evaluate the scope for improving the disease tolerance of spring barley. [source] Assessing the potential impact of salmon fisheries management on the conservation status of harbour seals (Phoca vitulina) in north-east ScotlandANIMAL CONSERVATION, Issue 1 2007P. M. Thompson Abstract Conservation efforts are often constrained by uncertainty over the factors driving declines in marine mammal populations. In Scotland, there is concern over the potential impact of unrecorded shooting of seals, particularly where this occurs near Special Areas of Conservation. Here, we show that the abundance of harbour seals Phoca vitulina in the Moray Firth, north-east Scotland, declined by 2,5% per annum between 1993 and 2004. Records from local salmon fisheries and aquaculture sites indicated that 66,327 harbour seals were shot each year between 1994 and 2002. Matrix models and estimates of potential biological removal indicate that this level of shooting is sufficient to explain observed declines. Nevertheless, uncertainty over the number and identity of seals shot means that other factors such as changes in food availability may be contributing. Recent conservation measures markedly reduced the recorded levels of shooting in 2003 and 2004. In 2005, a coordinated management plan was developed to protect salmon fisheries interests while minimizing impacts on local seal populations. Comprehensive monitoring of future population trends and improved regulation of culls are now required to provide more robust assessments of the impact of human persecution on harbour seal populations in the Moray Firth and in other parts of the UK. [source] Characterization of freshwater pearl mussel (Margaritifera margaritifera) riverine habitat using River Habitat Survey dataAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2003L.C. Hastie Abstract 1.The feasibility of using River Habitat Survey (RHS) data to describe freshwater pearl mussel (Margaritifera margaritifera) macrohabitat in the River Spey, north-east Scotland, was investigated. 2.Mussels were found to be positively associated with a number of RHS variables. These included: boulder/cobble river bed substrates, broken/unbroken standing waves (channel flow types), aquatic liverworts/mosses/lichens and broadleaf/mixed woodland/bankside tree cover. Negative associations with gravel-pebble/silt substrates and emergent reeds/sedges/herbs were also found. 3.Two binary logistic regression models, based on seven and four variables, respectively, were constructed in order to predict the presence/absence of mussels at any given site. Predictive success rates of 83% and 78% were achieved. 4.Another binary logistic regression model, based on four variables, was constructed in order to predict the occurrence of ,optimal' M. margaritifera habitat (overall mussel densities , 1 m,2). A predictive success rate of 83% was achieved. 5.The results indicate two potentially important applications of RHS for the conservation management of M. margaritifera: (1) for monitoring the effects of physical changes on extant mussel beds (and predicting their effects on mussel populations), and (2) for determining the habitat suitability of historically occupied sites for re-introductions. Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||