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561.
562.
Habitat restoration projects are often deemed successful based on the presence of the target species within the habitat; however, in some cases the restored habitat acts as an ecological trap and does not help to improve the reproductive success of the target species. Understanding wildlife–habitat relationships through precise measurements of animal behavior can identify critical resources that contribute to high quality habitat and improve habitat restoration practice. We evaluated the success of a restored piping plover (Charadrius melodus) breeding habitat in New Jersey, USA. We identified the major factors influencing foraging rates, compared foraging activity budgets over 3 yr at restored and natural habitats, and explored the potential of artificial tidal ponds as a viable restoration alternative. Adult foraging rates were higher in artificial pond and ephemeral pool habitats, during low tide, and after breeding activity ended. Adult foraging rates were impeded by the presence of people and vehicles within 50 m. Chick foraging rates were highest at artificial ponds and bay shores and lowest in dunes and on sand flats. Chick foraging rates were strongly hindered by the presence of corvids and the number of people within 50 m. In addition, at artificial tidal ponds, piping plovers spent more time foraging and less time engaged in defensive behaviors (vigilance, crouching, and fleeing) compared to other potential habitats. Our findings support the hypothesis that artificial tidal ponds are a valuable, perhaps superior, foraging habitat. Future beach restoration projects should include this feature to maximize habitat quality and restoration success. © 2011 The Wildlife Society. 相似文献
563.
This study analyzes the pollen counts obtained from the air of the greater Lyon (corresponding to the urban area of Lyon)
an area which has been overrun by ragweed in the last 40 years. Two periods are investigated, 1982–1989 and 1990–1995. The
year 1995 deserves specific attention because for the first time a campaign of ragweed eradication was launched in greater
Lyon. From the data of the 14 pollination seasons it was possible to define some parameters: subpathological risk period,
pathological risk period and the position and level of the pollen peak. Our study indicates the progression of the weed in
the infested area over the two periods. In 1995 a slight decrease in the pollen count was observed but this was followed by
a second peak probably related to later growth of some plants which had been cut. In this connection, 4 weeks weeding campaign
is not long enough and in the future a 6-week campaign without the use of weedkillers should be planned. Determining the parameters
of ragweed pollination every year will be useful both to patients and physicians concerned by allergy to ragweed pollen. According
to the level of the ragweed pollen in the air, the patients may take appropriate medication. This study emphasizes the necessity
to record air pollen concentrations over many years. In particular, the actual impact of cutting ragweed before pollination
on ragweed pollen counts can only be evaluated after several years of eradication. 相似文献