Management for TES species typically involves four steps that are often embedded into a larger conservation plan that includes ecosystem targets. First, managers assess the TES species occurring on the base. Depending on the current state of knowledge, this investigative stage could help identify TES species occurring on the base, identify population sizes and trends, map distributions and seasonal movements, and identify threats. The assessment may also look at species’ status off site to determine DoD’s management responsibility (for example, what proportion of a species’ range or population occurs on the base). Second, managers plan strategies to protect and, if needed to recover species to achieve specific management goals. Next, managers act to implement strategies. Finally, managers monitor for implementation of strategies, threat abatement (if needed), and the response of the target population. Depending on the monitoring results, strategies can be adjusted to increase success. The following sections describe details and tools used to carry out these basic management steps.
Determining TES species present on a base
The charismatic Threatened and Endangered species present on a base will likely be well known. Base managers will have dealt with these species for years. Lesser-known species, especially those that recently attained Candidate or Proposed ESA status may require field surveys to determine presence or absence on a base. Also, because of climate change, species that previously did not occur on a base may show up and make themselves at home.
Networking is a good way to stay on top of changing ESA status and species movements. A good relationship with the local FWS office is key to receiving alerts about species status. NatureServe Network Programs in the U.S. (sometimes referred to as “state natural heritage programs”), and the non-game offices of state fish and wildlife agencies are also good resources for species information.
The population of species found on bases can play an important role in influencing that species’ status or listing decision. If a base has good examples of habitat that has declined elsewhere, it may have an unusually healthy population of the species in question. And because the base is off limits to casual observers, scientists and biologists compiling the FWS Species Status Assessments to inform listing decisions may not know of that population. Additionally, base personnel may be unaware that a species is present until a proper survey is performed. The value in conducting a survey for a species under review is that it could reveal previously unknown healthy populations. This information could mean the species is less threatened than thought, tipping the balance away from the need for formal legal protection—a win for everyone.
Once the list of target species or a species group is compiled, the next step is to determine where to look for them. Knowledge of the species’ habitat requirements and a good vegetation map of the base can help to narrow down the search area. In the absence of a useful habitat description, plotting localities for the species from NatureServe Network Programs or online data aggregators such as Biodiversity Information Serving Our Nation (BISON) or Symbiota Collections of Arthropods Network on a vegetation map can give useful clues. Sometimes the notes associated with digital locality records include habitat description. A more powerful approach is to use a habitat model to predict where suitable habitat for the species occurs on a base (see below in Tools for Assessment).
- For field surveys, unless base personnel have experience surveying for a particular type of organism, a partnership with experts is essential to conducting the survey. Partners ideally have authoritative experience with a sensitive species and can perform field work using proper methods at an appropriate time of year under favorable weather conditions, and then report on whether a particular species does or does not occur on a base. Potential partners may include: Partners in Amphibian and Reptile Conservation (PARC)
- Partners in Flight (PIF) for birdsocal native plant societies for rare plants
- NatureServe Network Programs in each state (expertise is extensive for a wide range of organisms)
- Universities (varies, but universities with wildlife management programs are a good place to start). Biologists at these institutions might also be able to refer local contractors with expertise in surveying specific groups of organisms.
Tools for assessment
Once a TES species is documented to occur on a base, decisions about which management strategies will have the greatest chances of success will typically require more information about the population. This assessment step can answer the following questions:
- Where does the species occur?
- How much of the species’ global population occurs on my base?
- Is the population expanding or contracting?
- Is the population viable?
- Has the population undergone genetic bottleneck, leaving it with perilously poor genetic variation?
- How is climate change affecting the population?
- Are any diseases or invasive species affecting the population?
A brief discussion of some of the tools available to answer these questions follow. Most of the tools are outside the realm of expertise of base environmental personnel, so again partnerships with academic institutions (especially military-specific research programs such as the Center for the Environmental Management of Military Lands at Colorado State University) or a state NatureServe Network Program can be valuable.
Mapping the Distribution of Species
If a field survey confirmed the presence of the species on a base, an extension of the survey to all potential suitable habitats can inform a map of the distribution on the base. If no survey has been conducted, consider taking that step. Being able to map out locations of individuals, habitat patches, nest sites, or some other indication of the species’ presence on a base is a powerful tool for understanding potential conflict with other base objectives such as training and target practice, as well as for identifying management strategies. There are about as many ways to conduct surveys as there are species to survey for. As suggested above, in most cases establishing a partnership with a competent agency or contractor is the best way to have a base surveyed for a particular species or species group.
Prior to conducting a survey or in cases where the suitable habitat is too remote or impractical to survey on the ground, consider running a habitat model for the species (Guisan and Thuiller 2005). Habitat models, also known as species distribution models, use an algorithm, coordinates of where a species has been observed, and relevant spatial environmental data such as climate, soils, vegetation type, and topography to predict where suitable habitat for the species is distributed across the modeled area. The more accurate the locality data and the more tightly a species is associated with the environmental predictor variables, the better the model will perform at predicting where the species occurs. These models require experience, access to high-resolution spatial environmental data, and a computer facility to process the data. The outputs can be highly informative for directing survey efforts or understanding how much of the land and water area of a base supports habitat for a species.
Next Page: Management responsibility
Author
Bruce Young, Ph.D., Chief Zoologist and Senior Conservationist Scientist
NatureServe
Managing for Threatened, Endangered and At-Risk Species
Managing for Threatened, Endangered and At-Risk Species