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Restored and artificial wetlands do not support the same waterbird functional diversity as natural wetlands

The restoration of degraded areas and the creation of artificial ecosystems have partially compensated for the continuing loss of natural wetlands. However, the success of these wetlands in terms of the capacity of supporting biodiversity and ecosystem functions is unclear. Natural, restored, and artificially created wetlands present within the Doñana protected area were compared to evaluate if they are equivalent in terms of waterbird functional trait diversity and composition. Functional diversity measures and functional group species richness describing species diet, body mass, and foraging techniques were modelled in 20 wetlands in wintering and breeding seasons. Artificial wetlands constructed for conservation failed to reach the functional diversity of natural and restored wetlands. Unexpectedly, artificial ponds constructed for fish production performed better, and even exceeded natural wetlands for functional richness during winter. Fish ponds stood out as having a unique functional composition, connected with an increase in richness of opportunistic gulls and a decrease in species sensitive to high salinity. Overall, the functional structure of breeding communities was more affected by wetland type than wintering communities. These findings suggest that compensating the loss of natural wetlands with restored and artificial wetlands results in systems with altered waterbird?supported functions. Protection of natural Mediterranean wetlands is vital to maintain the original diversity and composition of waterbird functional traits. Furthermore, restoration must be prioritised over the creation of artificial wetlands, which, even when intended for conservation, may not provide an adequate replacement. informacion[at]ebd.csic.es: Almeida et al. (2020) Comparing the diversity and composition of waterbird functional traits between natural, restored, and artificial wetlands. Freshwater Biology DOI 10.1111/fwb.13618


https://onlinelibrary.wiley.com/doi/full/10.1111/fwb.13618
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Lifelong effects of trapping experience

Lifelong effects of trapping experience

Long-term monitoring of individually marked animals is usually required for reliable estimation of numerous life history parameters. However, capture, marking and manipulation can dramatically alter the animals' behaviour after capture, and thus affect subsequent recapture success. Here, a pied flycatcher population was used as an example to illustrate the sampling bias resulting from the repeated capture of free-ranging individuals. By using repeated measures of the same individuals obtained during our long-term survey, the interannual response of breeding adults to capture-related stress was specifically evaluated, measured as latency to enter nestboxes equipped with a swing-trap. Moreover, the changes in the mean and variance of bird age with varying trapping effort were examined using subsamples of the data set. Birds without any previous trapping experience entered nests more quickly than experienced ones, after controlling for other factors affecting latency, such as the sex, offspring quality and the order of capture relative to the other pair member. Birds' reluctance to enter the nest furthermore increased as the number of captures in previous years accumulated, implying that individual pied flycatchers became progressively more difficult to capture over the course of the study. These results indicate that repeated exposure to capture stress over an animal's lifetime may induce long-lasting behavioural modifications that may influence trappability of the older segments of the population. This may ultimately lead to sampling bias towards younger ages, especially when effort is limited. The study concludes that systematic age bias due to trapping experience can have important implications for the estimation of variation in a range of traits and should therefore be carefully checked in longitudinal studies. informacion[at]ebd.csic.es: Camacho et al (2017) Lifelong effects of trapping experience lead to age-biased sampling: lessons from a wild bird population.


http://www.sciencedirect.com/science/article/pii/S0003347217301938