Management of hunting activity to serve as a tool for sustainable development has become a key issue in conservation biology. However, little evidence is available showing positive impacts of hunting ...on ecosystem conservation, limiting its capability to be used as a conservation tool. We analysed hunting and its positive influence on the ecology and conservation of the griffon vulture (Gyps fulvus), a scavenger with a relevant function in the ecosystem, in the Cantabrian Mountains, NW Spain. Use of the area by vultures was addressed by looking for cliffs used as roosts or colonies, and consumption of game species by vultures was evaluated through field surveys and questionnaires to hunters. Results revealed a strong spatiotemporal adjustment in the use of the area by vultures and hunting events, especially of red deer and wild boar. Vultures occupied roosting sites very close to the main hunting sectors of these game species and often were seen consuming their carcasses. The spatiotemporal pattern of roost use by vultures strongly overlapped with hunting of red deer. The numbers of both red deer and wild boar hunting episodes within 3.5 km around the roosts were the best predictors of vulture occurrence and number. Our estimates show that hunting could feed around 1,800 vultures/6 months. Hunting can thus influence species at the top of the ecosystem (scavengers) and could aid sustainable management of griffon vulture populations, reconciling hunting and conservation. However, negative and positive impacts should be taken into account simultaneously for an overall evaluation of hunting on ecosystem conservation.
107 eggs of Canada geese from clutches within the environs of the recreational area of "Saaler Mühle" in North Rhine-Westphalia were morphometrically, microbiologically, and serologically analyzed. ...Investigations for the following pathogens or their antibodies were conducted: (i) zoonoses (Salmonella sp.,Campylobacter sp.,Chlamydia sp.) (ii) the antibodies to or the pathogens causing epidemics (virus of Newcastle Disease, Influenza A-Virus of haemagglutinin (HA-)- Subtypes H5 and H7); (iii) pathogens or their antibodies of primary diseases of waterfowl (Riemerella sp.,Pasteurella sp.,Escherichia coli, mold and yeast fungi, Paramyxovirus for the Serotypes 4 and 6, Egg-Drop Syndrome 1976, and duck plague herpes virus. Salmonella could not be culturally isolated from embryos, egg yolks, and egg membranes. Neither could Chlamydia be verified using HELA cell cultures. The isolation of pathogens for virally caused animal epidemics (Newcastle Disease and Fowl Pest was unsuccessful. A proof of the presence of antibodies to Newcastle Disease could only be shown in samples of egg yolks from 9 eggs. Antibodies to the Influenza A-Virus of the HA-Subtype H5 could only be determined in the yolk of one egg, and antibodies against the Influenza A-Virus HA -Subtype H7 could only be verified from 2 eggs. The cultural isolation of pathogens causing primary bacterial diseases of waterfowl could only be verified forPasteurella sp. (one egg),Escherichia coli (one egg), andStaphylococcus sp. (23 eggs). Various molds were isolated from 6 eggs. The cultural propagation of yeasts was unsuccessful. From one egg (Nr. 102) a virus belonging to the group of avian reoviruses was isolated. Antibodies against the Paramyxovirus Serotype 4 could not be detected. In 4 egg yolk samples antibodies against the Paramyxovirus Serotype 6 were found. Antibodies against the Egg-Drop Syndrome-1976 Virus were found in 20 egg yolk samples. A total of 14 yolk samples contained antibodies against the herpes virus of duck plague. The Hepatitis B virus of geese could not be determined with PCR. No pathogenic agents causing infectious diseases harmful to people were found. The demonstrated pathogens/antibodies of waterfowl epidemics and diseases present a potential danger for domestic poultry as well as for a few other species of wild birds. Careful observation of the Canada geese population and further investigations are necessary.PUBLICATION ABSTRACT
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