Summary

Description

Considering the information provided in the previous section, the objective of the present investigation is to examine foraging habits of wood storks, as well as contaminants in dead nestlings from an urban colony and in prey and sediments from waterbodies used by foraging wood storks. Given the mobility of wading birds, the loss of natural wetlands, the gain of manmade water bodies, and the negligible contaminant risks, enhancement of manmade water bodies may assist efforts to conserve species such as wood storks. Enhancements could include stocking of prey fish, decreasing slopes andor installing littoral, and controlling emergent aquatic vegetation to increase their ability to forage. Federal agencies under section 7a1 of the ESA are authorized to carry out programs to further the conservation of threatened and endangered species. Under the FWCA and MBTA, the USFWS can submit comments to project proponents for furthering conservation and minimizing impacts associated with proposed activities. To illustrate, Federal agencies that have permitting programs associated with retention ponds could offer incentives or establish requirements for ponds to be constructed in a way that would enhance their use by wading birds such as wood storks. Although Martin 2010 suggested steep slopes should be maintained on golf course ponds because those types of manmade water bodies had higher concentrations of certain contaminants compared to the other water bodies, Martin 2010 also stated that exposure to contaminants across all water bodies, including golf, course ponds was low and there was little risk of adverse effects to wood storks that foraged on prey from the water bodies. The USFWS has authorities under section 7a2 and 10 of the ESA to require project proponents to develop and implement reasonable and prudent measures to minimize take of federally threatened or endangered species, but the USFWS has to be reasonably certain that the area is occupied or used by the species, and that the projects direct and indirect effects are going to take individuals of that species, This investigation supports the first of these two requirements, but not the second. In regard to the contaminantrelated effects on wood storks, the present investigation indicates that contaminant exposure is not reasonably certain to result in take of wood storks that forage in the types of manmade water bodies that are represented in the present investigation; and therefore, the USFWS could not require changes to the design of new water bodies or modification of existing water bodies. During section 7a2 consultations, the USFWS can, however, make conservation recommendations which are not mandatory to project proponents that would aid in the conservation of threatened and endangered species by enhancing or discouraging the use of manmade water bodies by wading birds. Depending on the situation, these recommendations could include the stocking of fish, creation of littoral zones, and other activities that would increase the use of the retention ponds by wading birds; or conversely, include measures to discourage bird use. In a broader sense, it should be noted that contaminant and noncontaminantrelated risks are considered during ESA consultations and may drive decisions regarding whether or not to enhance manmade water bodies for wading birds. For example, the proximity of retention ponds to roads and highways is a concern because of potential automobile strikes. In closing, development of a document to guide decisions regarding the design and management of retention ponds and other manmade water bodies may be useful in streamlining regulatory procedures and aiding the conservation of wood storks and other wading birds.