Development of Multi-tiered Wetland Assessment Methods for Monitoring Wetland Condition Amy Deller Jacobs DE Department of Natural Resources and Environmental Control

Delaware Wetland Status and Trends 54% lost since 1780’s Most of loss due to ditching and channelization and direct conversion to ag of nontidal wetlands

From there was an 80% reduction in loss from previous decade From Delaware lost 2000 acres Delaware Wetland Status and Trends

Why Monitor Condition? Evaluate what functions are being performed and at what level Determine stressors Gain information to guide restoration and enhancement Meet requirements of TMDL lawsuit/ Required under Clean Water Act

LEVEL 1 GIS Platform No Fieldwork LEVEL 2 Rapid Assessment Some Fieldwork LEVEL 3 Intensive Field Sampling Level of Effort Increases Level of Detail Decreases Multiple Levels of Assessment

Nanticoke Wetland Study

Overall Success Rate Permission for Access N = % 17% Granted No Contact Denied 38% No Contact Granted Denied 38% 44% 18% N = 321 TNC STATE

Success Rate with Contact Excluding Public Lands N = 227 Percent 67% 33%

Hydrogeomorphic Models Data Variable Function

HGM Function Wildlife Habitat (Vdisturb + ((Vtba + Vtden)/2) + Vshrub + Vsnag)/4 Results are between 0 and 1

Total Effort 24 man-hours

Rapid Assessment (Level II) Development of a Rapid Assessment Method Evaluates condition and can distinguish various levels Requires a site visit No detailed data collected

Based on HGM models and field experience Evaluates stressors present at a site Weights stressors according to their impact on 4 categories (hydrology, habitat, biogeo cycling, and landscape) Provides one overall score of the condition of the wetland Rapid Assessment (Level II)

Mowing-3 Farmed-9 Grazing-3 Forest harvesting (>50% of stand) Recovered0 Recovering-5 Recent-7 Cleared not recovering-7 Excessive herbivory Presense of invasive spp. Dominate the site-7 Do NOT dominate the site-2 Chemical defoliation-3 Managed or converted to pine-5 Burned-3 Trails Garbage/ isolated dumping Other Subtotal Habitat Community 10 + sum of above, if score <0 record 0 Habitat Category

Rapid Assessment (Level II) Total Score (Hydrology/10) + (Hydrology/10)*(Biogeo/10)) + (Habitat/10) + ((Habitat/10)*(Landscape/10))

Current projects Validating with HGM (level III) Determining sensitivity of methods Evaluating transferability to other areas of the state Rapid Assessment (Level II)

Comparison of Effort to sample 50 sites 4 hours/ site 4 person crew 25 days(2 sites/day) 100 person-days Several hours office work 2 hours/ site 2 person crew 12.5 days (4 sites/ day) 25 person-days Minimal office work Level III Level II

LEVEL 1 GIS Platform No Fieldwork LEVEL 2 Rapid Assessment Some Fieldwork LEVEL 3 Intensive Field Sampling Level of Effort Increases Level of Detail Decreases Multiple Levels of Assessment

Landscape Level Assessment (I) Inventory – status and trends Updated wetland maps –Including HGM modifiers –Provide additional information Landscape analysis –Inferring condition based on indicators in surrounding landscape

Stepwise multiple regression results for flat HGM functions Variables FunctionNo.Namesr 2 * Biogeochemistry5ex100 –ex500 –FOREVER100 –GRASS1000 FOREST Habitat5+nat100 –nimpound1000 –FOREVER 100 –GRASS1000 FOREST Hydrology3-ex100 –nat1000 +FORDEC Plant2-ex1000 +FORDEC * n=89, p< for all models

Stepwise multiple regression results for riverine HGM functions Variables FunctionNo.Namesr 2 * Biogeochemistry3-ex100 +nat1000 –DEVTOT Habitat2-ex100 +nat Hydrology5-ex100 +nat1000 +FOREST100 +FOREST FORDEC Landscape6-ex100 –ex1000 +nat1000 –CROP100 –DEVTOT1000 +FOREVER Plant2-ex500 –DEVTOT * n=54, p< for all models

Assess loss and condition by subclass Determine Spatial Need to Restore Function Prioritize Restoration and Protection Projects Monitor to Determine Progress and Reassess Priorities Determine Stressors