Mitochondrial DNA control region polymorphisms: genetic markers for ecological studies of marine turtles

We describe a rapid and sensitive method for the detection of population-specific genetic markers in mitochondrial DNA (mtDNA) and the use of such markers to analyse population structure of marine turtles. A series of oligonucleotide primers specific for the amplification of the mtDNA control region in Cheloniid turtles were designed from preliminary sequence data. Using two of these primers, a 384–385-bp sequence was amplified from the 5′ portion of the mtDNA control region of 15 green turtles Chelonia mydas from 12 different Indo-Pacific rookeries. Fourteen of the 15 individuals, including some with identical whole-genome restriction fragment patterns, had sequences that differed by one or more base substitutions. Analysis of sequence variation among individuals identified a total of 41 nucleotide substitutions and a 1-bp insertion/deletion. Comparison with evidence from whole-genome restriction enzyme analysis of the same individuals indicated that this portion of the control region is evolving approximately eight times faster than the average rate and that the sequence analysis detected approximately one fifth of the total variation present in the genome. Restriction enzyme analysis of amplified products from an additional 256 individuals revealed significant geographic structuring in the distribution of mtDNA genotypes among five of the 10 rookeries surveyed extensively. Additional geographic structuring of genotypes was identified through denaturing gradient gel electrophoresis (DGGE) of amplified products. Only two of the 10 rookeries surveyed could not be differentiated, indicating that the Indo-Pacific C. mydas include a number of genetically differentiated populations, with minimal female-mediated gene flow among them. Important applications for genetic markers in the conservation and management of marine turtles include the identification of appropriate demographic units for research and management (i.e. genetically discrete populations) and assessment of the composition of feeding and harvested populations.     

Changes in the crustacean zooplankton community of Harp Lake, Canada, following invasion by Bythotrephes cederstrœmi

1. Detecting the impacts of invading Bythotrephes cederstrœmi (Crustacea, Onychopoda, Cercopagididae) on zooplankton in North American lakes has been hampered by the brevity of pre-invasion data, and by the difficulty of distinguishing the effects of the invader from other stresses. The data from Harp Lake in Ontario, Canada, circumvent these difficulties. Bythotrephes appeared in the lake in 1993. There is a 15-year pre-invasion data set, and no significant complicating concurrent stresses.
2. The species composition and the size structure of the crustacean zooplankton community of Harp Lake changed after the invasion. Several small species either declined dramatically in abundance (e.g. Bosmina longirostris , Tropocyclops extensus ) or disappeared ( Chydorus sphaericus , Diaphanosoma birgei , Bosmina ( Neobosmina ) tubicen ). In contrast the abundance of the larger cladocerans Holopedium gibberum and Daphnia galeata mendotae and the hypolimnetic copepod Leptodiaptomus sicilis increased. Several univariate and all multivariate summarizations of zooplankton abundance, biomass and size structure highlighted the uniqueness of the post-invasion community.
3. The alterations in the zooplankton community could not be attributed to changes in lake acidity, thermal regimes, penetration by ultraviolet light, nutrient status, fish stocking or the abundances of native invertebrate predators, but they were correlated with Bythotrephes abundance, both within and among years. Hence, we hypothesize that the invasion by Bythotrephes has significantly altered the crustacean zooplankton community of Harp Lake.     

An Overview of Metal Pollution in the Western Harbour of Alexandria,Egypt

Limited data are available on the concentration of metals in sediments in the Western Harbour of Alexandria. The most comprehensive record is from a survey conducted more than a decade ago. Industrial and human activities in and around this area have increased dramatically in the last 20 years. The purpose of this study was to determine the concentrations of heavy metals in surfacial bottom sediments of the harbor, to assess their potential biological effects and to identify their possible sources. Sediment samples from 21 stations throughout the harbor were analyzed for grain size, total organic carbon content (TOC), and metals (Al, As, Ba, Be, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Se, Sn, V, and Zn) to assess the extent of contamination in the area. The results indicated that concentrations of metals in the sediments varied widely depending on the location. High levels of metals were observed in the Arsenal Basin and the outfall area of El Mahmoudiya Canal in the inner harbor. The concentrations of metals were found to be higher than those recorded in the previous study. However, with some exceptions, most of the changes in the metal concentrations could be accounted for by the variations in aluminum, which represents the variations in mineralogy and grain size, indicating that the majority of the metals were of “natural” origin. The present data were also compared with results from other areas.     

Effects of Winter-Feeding on Mule Deer in Northern Utah

Abstract: During severe winters, mule deer (Odocoileus hemionus) concentrated on ranges in poor condition can experience high mortality. Winter-feeding programs have been implemented to mitigate this mortality. We studied effects on body condition, mortality, fawn production, and migration of mule deer following winter-feeding in the Cache-Wasatch Mountains of northern Utah, USA. Fed deer exhibited 12% higher live body-condition indices both years (main effect feed: F_1,7.32 = 5.39, P = 0.052), lower mortality (33% vs. 55%: χ²₁= 4.58, P < 0.05), and produced more fawns (19 fawns:18 fed F vs. 11 fawns:12 nonfed F; t_27.2 = 2.20, P < 0.036) than nonfed deer. Fed deer migrated later in spring 2004 (x̄ = 13 Apr) than nonfed deer (x̄ = 24 Mar; t₃₄= 3.25, P = 0.003). Fed deer spent more time on winter range in 2003-2004 (x̄ = 157 d) than nonfed deer (x̄ = 121 d; t20 = 3.63, P = 0.002), and more time on winter range for both winters combined (fed deer x̄ = 321 d, nonfed deer x̄ = 257 d; t₂₇ = 3.29, P = 0.003). Concomitantly, wildlife managers need to recognize that any possible benefits accrued to mule deer populations in terms of increased nutritional status as a result of winter-feeding programs may be mitigated by altered timing of migration and increased duration of use of seasonal ranges by fed deer.     

Can Public Meetings Accurately Reflect Public Attitudes Toward Wildlife Management?

Abstract: State wildlife agencies often use input obtained through public meetings to develop management policies. Because public meetings can be dominated by single stakeholder groups, these policies may not reflect the attitudes of new wildlife stakeholders. In 2000 the Utah Wildlife Board, after a series of public meetings, adopted a statewide policy for winter-feeding mule deer (Odocoileus hemionus). The policy was implemented by the Utah Division of Wildlife Resources from 2001 to 2007 in Cache County of northern Utah, USA. In 2007, we surveyed Utah households representing metropolitan, nonmetropolitan, and Cache County residents (n = 1,800) to evaluate whether the winter-feeding policy reflected the attitudes of all wildlife stakeholders. Survey respondents, regardless of residence strata, believed winterfeeding programs were essential for managing mule deer in Utah (χ²₆ = 7.02, P = 0.32). However, most respondents were reluctant to support feeding programs at the expense of habitat restoration projects (χ²₆ = 11.64, P = 0.07). Our results suggest that the winter-feeding policy represented the attitudes of the Utah residents surveyed, though few had participated in its development. Respondents' strong utilitarian attitudes toward wildlife (e.g., strong support for hunting and feeding) influenced those respondents' perceptions of the policy. Given the effects of increased urbanization on utilitarian attitudes toward wildlife in many parts of the United States, coupled with decreasing numbers of traditional wildlife stakeholders, state wildlife agencies should continually reevaluate their public involvement processes to ensure new wildlife stakeholders' attitudes and concerns are represented.     

Predicting small‐mammal responses to climatic warming: autecology,geographic range,and the Holocene fossil record

Forecasting how species will respond to climatic change requires knowledge of past community dynamics. Here we use time‐series data from the small‐mammal fossil records of two caves in the Great Basin of the American West to evaluate how contrasting and variable local paleoclimates have shaped small‐mammal abundance dynamics over the last ～7500 years of climatic change. We then predict how species and communities will respond to future scenarios of increased warming and aridity coupled with continued spread of an invasive annual grass (Bromus tectorum). We find that most community‐level responses to climatic change occur in the mammalian abundance structure at both sites; the dominance of the community by individuals from species with a southern geographic affinity increases with climatic warming. This suggests that responses occurred in situ rather than by the immigration of new taxa over this time interval. Despite predictability at the community‐scale, species‐level relationships between abundance and climate are variable and are not necessarily explained by a species' geographic affinity. Species present at both sites, however, exhibit remarkably similar responses to climate at each site, indicating that species autecology (specifically dietary functional group) is important in determining response to climatic warming. Regression‐tree analyses show remarkable concordance between the two cave faunas and highlight the importance of a granivorous dietary strategy in this desert ecosystem. Under projections of increased temperature and decreased precipitation over the next 50 years, our results indicate that granivores should thrive as communities become more dominated by individuals with a southern geographic affinity. Granivores, however, are negatively impacted by the invasion of cheatgrass. The last century of anthropogenic impacts has thus placed granivores at a greater risk of extinction than predicted under climate‐only scenarios.     

Costs and benefits of cervical screening IV: valuation by women of the cervical screening programme

OBJECTIVES: To assess the value of the cervical smear test to women, taking account of the positive and negative aspects of the cervical screening service. DESIGN: A postal survey. SETTING: Tayside Health Board region of Scotland. PARTICIPANTS: A sample of 2000 women aged 20-59. MAIN OUTCOME MEASURES: Maximum willingness to pay (WTP) for a cervical smear test. RESULTS: Women were prepared to pay 50.20 British pounds per smear on a 3-yearly basis. Willingness to pay was positively related to income, but unrelated to age and whether or not the respondent had previously had a smear. CONCLUSIONS: Previous studies have estimated the cost per screen or cost per life year saved by cervical screening. This study used the economic instrument of WTP to take account of other potential (dis)benefits to women. The value women place on having a smear was more than the cost to the National Health Service (NHS) of providing the service. The output of a WTP study is potentially useful at the policy level. Future work should explore both the value of alternative approaches to cervical screening, and the value of competing health care interventions.