The Experts below are selected from a list of 44106 Experts worldwide ranked by ideXlab platform

E. Huttinger - One of the best experts on this subject based on the ideXlab platform.

Scott P Schell - One of the best experts on this subject based on the ideXlab platform.

D. Massenet - One of the best experts on this subject based on the ideXlab platform.

Gerald Louette - One of the best experts on this subject based on the ideXlab platform.

  • Combating adult invasive American bullfrog Lithobates catesbeianus
    European Journal of Wildlife Research, 2014
    Co-Authors: Gerald Louette, Sander Devisscher, Tim Adriaens
    Abstract:

    American bullfrog Lithobates catesbeianus is considered as one of the world’s worst alien invasive species. Currently, the species is present over almost all continents and is suspected to cause substantial ecological damage. Knowledge about its population density, as well as catchability of the species with commonly used sampling gear, is very useful when considering the development of sound population control programs. Using the multiple Mark-Recapture Method, we investigated the density, sex ratio, and mobility of an adult bullfrog population inhabiting several neighbouring small shallow ponds at the peak of reproduction (mid June–mid July). We estimated the density at 4.3 adults/100 m shore length and the sex ratio (males/females) to 1.64. On average, males and females moved 25 and 83 m, respectively. Catchability of adults, using one double fyke net for 24 h, was rather constant and equalled 0.7 % of the population size. At first sight, this capture technique seems not to generate large-scale adult removal. However, as a companion study revealed that double fyke nets are highly effective for capturing tadpoles, control or even eradication of isolated populations may be enhanced when this proportion of the adult segment is equally removed.

  • control of invasive american bullfrog lithobates catesbeianus in small shallow water bodies
    European Journal of Wildlife Research, 2013
    Co-Authors: Gerald Louette, Sander Devisscher, Tim Adriaens
    Abstract:

    Setting up cost-efficient control programs for alien invasive species requires the development of adequate removal Methods in combination with insights in population size and dynamics. American bullfrog Lithobates catesbeianus is an alien invasive species, which is suspected to cause substantial ecological damage around the globe. However, control of bullfrog populations is difficult, as no conclusive management measures have yet been determined. We investigated how double fyke nets could contribute to bullfrog management by assessing the tadpole population size in 10 permanent small shallow water bodies. Two population size estimate Methods were applied, being the catch–depletion and mark–recapture Method. Catchability of bullfrog tadpoles proved to be very consistent over ponds and Methods, with one catch per unit of effort (one double fyke net for 24 h) retaining on average 6 % of the tadpole population. Population density varied considerably among ponds, ranging from 950 to 120,804 larger tadpole individuals/ha. Using these insights in developing a cost-efficient eradication program for the species, we projected the number of catch efforts needed to reduce tadpole numbers to a threshold that more than likely affects final bullfrog population size. Predictions indicated that for the specified thresholds the use of eight double fyke nets at a time is most cost-efficient in high abundance populations, while using five double fyke nets seems most suitable in low abundance populations. What the exact threshold number of remaining tadpole individuals should be is uncertain, but forecasts demonstrate that only half of the budget would be needed when aiming at a drop to fewer than 100 remaining tadpoles than when a decrease to fewer than 10 remaining tadpoles is pursued. Given the fairly limited cost of bullfrog management with double fyke nets, however, it may be worthwhile to fully reduce the tadpole population.

  • assessment and control of non indigenous brown bullhead ameiurus nebulosus populations using fyke nets in shallow ponds
    Journal of Fish Biology, 2006
    Co-Authors: Gerald Louette, Steven Declerck
    Abstract:

    In order to evaluate fyke nets as a tool for population assessment and mass removal of brown bullhead Ameiurus nebulosus populations, small, shallow ponds were sampled during late summer in 1999 and 2000. Catch efficiency, species and size selectivity of fyke nets were investigated with the Mark-Recapture Method. Two different strategies were applied: (1) on six occasions, the Mark-Recapture Method was applied to entire populations, and (2) in six other cases, sampling was done in two replicated enclosed areas (625 m 2 ). When applied to entire populations, fyke nets were found to be size selective, and capture efficiency significantly increased with standard length. Conversely, no size selectivity of fyke nets was found in enclosed areas. Sampling in replicated enclosures yielded reproducible estimates of population density and biomass. The results suggest that double fyke nets, when combined with the Mark-Recapture technique, are a very useful tool for the efficient and reliable assessment of brown bullhead populations. The results of the study also suggest that double fyke nets may potentially be a cost-effective tool for the mass removal of non-indigenous brown bullhead populations.

  • Assessment and control of non‐indigenous brown bullhead Ameiurus nebulosus populations using fyke nets in shallow ponds
    Journal of Fish Biology, 2006
    Co-Authors: Gerald Louette, Steven Declerck
    Abstract:

    In order to evaluate fyke nets as a tool for population assessment and mass removal of brown bullhead Ameiurus nebulosus populations, small, shallow ponds were sampled during late summer in 1999 and 2000. Catch efficiency, species and size selectivity of fyke nets were investigated with the Mark-Recapture Method. Two different strategies were applied: (1) on six occasions, the Mark-Recapture Method was applied to entire populations, and (2) in six other cases, sampling was done in two replicated enclosed areas (625 m 2 ). When applied to entire populations, fyke nets were found to be size selective, and capture efficiency significantly increased with standard length. Conversely, no size selectivity of fyke nets was found in enclosed areas. Sampling in replicated enclosures yielded reproducible estimates of population density and biomass. The results suggest that double fyke nets, when combined with the Mark-Recapture technique, are a very useful tool for the efficient and reliable assessment of brown bullhead populations. The results of the study also suggest that double fyke nets may potentially be a cost-effective tool for the mass removal of non-indigenous brown bullhead populations.

N. Jouanard - One of the best experts on this subject based on the ideXlab platform.