Redundancy

At the species level, the PCC comprises 13 populations. These populations are broken into an eastern group of five populations and a western group of eight populations based on the genetics of PCC and its geographic distribution. Currently, four populations, all in the west, are in the low condition, including the two that were excluded from future condition analysis because of inadequate data. These populations represent 31% of the known populations overall and 50% of the western group, and, although still in existence, they may not contribute to the future redundancy of PCC, because the populations are already experiencing genetic drift and the habitat that supports them is susceptible to the future development.

All future scenarios are predicted to have a negative impact on the redundancy of PCC during the 50 year time horizon (Table 5.7). Under the Status Quo scenario, 62% of populations are in low condition by 2050; this percentage increases to 69% under the Intermediate Development scenario and, in the worst case, to 77% under the High Development scenario. The greatest loss of redundancy for PCC is predicted to occur in the western group. In this group, 100% of the populations are in low condition by 2050 under the High Development scenario and 88% under the other two scenarios. In the eastern group, three populations are predicted to remain strongholds for PCC, although this is only 60% of the eastern group remaining.

 

Table 5.7. Change in redundancy of Panama City crayfish populations under the three future scenarios. See Table 3.7 in Chapter 3 for condition descriptions.
Region
Population Condition
Year
Status Quo
Intermediate Development
High Development
Overall High 2030 3 3 2
2050 3 3 2
2070 3 2 1
Moderate 2030 3 3 3
2050 2 1 1
2070 2 2 2
Low 2030 7 7 8
2050 8 9 10
2070 8 9 10
West High 2030 0 0 0
2050 0 0 0
2070 0 0 0
Moderate 2030 2 2 2
2050 1 1 0
2070 1 1 0
Low 2030 6 6 6
2050 7 7 8
2070 7 7 8
East High 2030 3 3 2
2050 3 3 2
2070 3 2 1
Moderate 2030 1 1 1
2050 1 0 1
2070 1 1 2
Low 2030 1 1 2
2050 1 2 2
2070 1 2 2