TWS and Chapters Comment on Wetland Determinations

The Wildlife Society, in partnership with the Iowa, North Dakota, and South Dakota TWS Chapters, and several other conservation and sportsmen’s groups has signed onto a letter providing comments to the Natural Resources Conservation Service’s (NRCS) proposed changes to State Offsite Methods (SOSM) for wetland determinations and mapping.

Agricultural producers that are voluntarily participating in NRCS and Farm Service Agency (FSA) programs must comply with wetland conservation provisions, which prohibit both converting wetlands to allow for agricultural production and producing agricultural commodities on a converted wetland. Non-compliance can affect producer’s ability to receive conservation program benefits. The proposed changes to SOSM would affect wetland mapping and wetland determinations in Iowa, Minnesota, North Dakota, and South Dakota and may alter which areas can be used for agricultural production while remaining in compliance with these conservation provisions.

The goal of the letter is to ensure that the proposed changes maintain the same accuracy in providing data for wetland determination as previous wetland mapping procedures and are not biased against seasonal and temporary wetlands. The Prairie Pothole Region (PPR) includes parts of the four states covered by the proposed SOSM changes. While the majority of PPR wetlands are seasonal or temporary in nature, they are critical in supporting North America’s waterfowl populations.

Use of late-season imagery and methods such as using wetness signature thresholds for wetland determinations may underestimate the size or totally omit the detection of some seasonal or temporary wetlands. The letter requests that the NRCS field verify the outlined methods outlined in the proposed SOSM and collect spring imagery, particularly in the PPR. While the FSA’s late-season imagery is sufficient for crop-monitoring purposes, it has major limitations in seasonal wetland mapping. Early-season imagery is more suitable for identifying temporary and seasonal wetlands. Proper determination and mapping of these areas is critical to preventing further conversion and loss of wetlands in the PPR.

The proposed changes for each state are available from the NRCS. The comment period on the proposed changes has recently closed.