Potential Future Sea Level Rise

To update and confirm this earlier work (Reese et al. 2013, Hocter 2014), we used two products to map predicted future changes due to sea level rise in 2025, 2050, and 2075 under a low (0.5 m) and high scenario (2.0 m) (Figure 4.2). We used the University of Florida digital elevation sea level rise model to predict habitat loss (Hocter 2014). This model predicts inundation changes based on elevation. We also used the Sea Level Rise Affecting Marshes Model (SLAMM) to predict changes in SLR that would affect habitat suitability inland from inundated areas (Clough et al. 2010). Using a 5-30 m pixel size, SLAMM simulates the dominant process involved in wetland conversions and shoreline modifications during long-term sea level rise. We assumed these vegetation changes would adequately represent the water quality changes from salt water intrusion that would affect crayfish persistence in affected areas. We looked at overall changes in habitat rangewide as well as within the suitable habitat supporting each individual population.

Overall, little suitable habitat for PCC will be affected by SLR, which confirms the earlier work of Hocter et al. (2014). By the year 2075, suitable habitat (in terms of suitable acres of core and secondary soils) within the range of PCC is predicted to be reduced by 1.28 ac (0.01%) with 0.5 m SLR and 40.2 ac (0.26%) with 2.0 m SLR (Table 4.1). However, two known populations were affected by SLR, Deer Point and Airport North (Table 4.2; Figure 4.3, Figure 4.4), which respectively sustained a 21.02 and 5.89 ac loss of suitable habitat by the year 2075 with 2.0 m SLR.

Projected habitat loss from sea level rise
Figure 4.3. Projected future habitat change for the Panama City crayfish rangewide in the year 2075 with a 0.5m (dark red) and 2.0 m (green) sea level rise. Only two populations, Airport North and Deerpoint showed loss of habitat due to sea level rise.
Table 4.1. Projected future suitable habitat (ac) supporting the Panama City crayfish rangewide as affected by sea level rise (SLR) based on SLAMM.
Predicted SLR
Soils
Base
2025
2050
2075
0.5 m Undeveloped – Secondary Soils 9682.74 9682.35 9682.35 9681.68
Undeveloped – Core Soils 5654.72 5654.67 5654.67 5654.5
Total 15337.46 15337.02 15337.02 15336.18
2.0 m Undeveloped – Secondary Soils 9682.74 9682.07 9670.51 9649.77
Undeveloped – Core Soils 5654.72 5654.56 5652.94 5647.49
Total 15337.46 15336.63 15323.45 15297.26
Table 4.2. Projected future suitable habitat (ac) supporting the two populations affected by sea level rise (SLR) based on SLAMM.
Predicted SLR
Site
Soils
Base
2025
2050
2075
0.5 m Deer Point Undeveloped – Secondary Soils 585.51 585.34 585.34 585.34
Undeveloped – Core Soils 258.09 258.09 258.09 258.09
Total 843.6 843.43 843.43 843.43
Airport North Undeveloped – Secondary Soils 9.51 9.17 9.17 9.17
Undeveloped – Core Soils 9.01 9.01 9.01 9.01
Total 18.51 18.18 18.18 18.18
2.0 m Deer Point Undeveloped – Secondary Soils 585.51 584.79 581.06 572.11
Undeveloped – Core Soils 258.09 258.03 256.25 250.47
Total 843.6 842.82 837.32 822.58
Airport North Undeveloped – Secondary Soils 9.51 8.9 8.56 7.12
Undeveloped – Core Soils 9.01 8.84 7.78 5.5
Total 18.51 17.74 16.35 12.62
Sea level rise effects on two PCC populations
Figure 4.4. Projected future habitat change in the year 2075 with a 0.5m (dark red) and 2.0 m (light red) sea level rise for the two affected populations.