1. Utilization of Benthic Invertebrates as Salinity Indicators in South Florida Rivers, Lessons from the Peace and Alafia Rivers Utilization of Benthic Invertebrates as Salinity Indicators in South Florida Rivers, Lessons from the Peace and Alafia Rivers Jim Culter Mote Marine Laboratory November 2013 Caloosahatchee Science Workshop

2. Objectives   Peace & Alafia River Projects, Large & Intensive   Determine benthic components that will have greatest utility for a possible long-term monitoring program. Species, communities, habitats or strata.   Evaluate relationships between the distribution and abundance of important benthic components and salinity.   Conclusions Transferrable to Caloosahatchee River?

3. When Peace River   November 1998 end of wet season,   January 1999winter dry season,   March 1999spring dry season,   April 1999spring very dry season   June 1999end of dry season. Alafia River  May 1999very low flow  September 2001end normal wet season

4.  Peace River – “Healthy River” Mollusk survey – 61 sites, 2 visits Mollusk survey – 61 sites, 2 visits 17,000 specimens17,000 specimens Infauna – 12 defined areas, 1,450 samples Infauna – 12 defined areas, 1,450 samples 4 zones intertidal / subtidal + 3 creeks + 1 SAV site4 zones intertidal / subtidal + 3 creeks + 1 SAV site 5 visits – 1 wet season, 4 dry season5 visits – 1 wet season, 4 dry season Each area – 10 cores, 10 sweep nets, 1AS/kmEach area – 10 cores, 10 sweep nets, 1AS/km + 120 sediment samples for granulometry+ 120 sediment samples for granulometry 60,936 benthic specimens60,936 benthic specimens 314 species314 species Level of Effort

5.  Alafia River – “Impaired River” Molluscs – 37 sites, 2 visits, 20 species Molluscs – 37 sites, 2 visits, 20 species Infauna – 17 defined areas, 298 samples Infauna – 17 defined areas, 298 samples 2 Hillsborough Bay locations, 15 River locations2 Hillsborough Bay locations, 15 River locations 2 visits – 1 wet season, 1 dry season2 visits – 1 wet season, 1 dry season Each area – 7 grabs & 2 sweep nets per seasonEach area – 7 grabs & 2 sweep nets per season 120 sediment samples for granulometry120 sediment samples for granulometry 16,266 benthic specimens16,266 benthic specimens 222 species dry season, 132 species wet season222 species dry season, 132 species wet season Level of Effort

6. Level of Effort – 1994-1995  Caloosahatchee River – “Impaired River” Infauna – 4 locations, 12 sample periods Infauna – 4 locations, 12 sample periods 192 samples 192 samples 219 species identified from 26,269 organisms 219 species identified from 26,269 organisms

7. Biologically Relevant Salinity Zones (NOAA) used for strata for Peace River study  Zone I≤ 0.5 PSUfreshwater  Zone II> 0.5 to ≤ 8.0  Zone III > 8.0 to ≤ 16.0  Zone IV > 16.0 PSU estuarine

8. Peace River Zone Characteristics

9. Alafia River

12. Alafia River Taxa ranked by abundance vs. weighted center of salinity.

13. Alafia River Alafia River Area downstream to upstream.

14. Caloosahatchee River Substrate Dial Cordy and Associates, Inc. 2012

19. Observations  Benthic fauna – species rich & abundant  Life history details for most species sparse  Epifaunal transients very important to fisheries  Seasonal movement upstream important

20. Observations, continued.  Intertidal river habitat is important  Rare taxa important? But not useful…  Abundant taxa too plastic?  High spatial and sample variance Large sample numbers needed to detect differences Large sample numbers needed to detect differences  Molluscs (other than oysters) Point in time collection ≠ species spatial domain. Point in time collection ≠ species spatial domain. 70% more species in Peace than Alafia *. 70% more species in Peace than Alafia *.

21. Observations, continued.  Molluscs (other than oysters) Point in time collection ≠ species domain Point in time collection ≠ species domain 70% more species in Peace than Alafia * 70% more species in Peace than Alafia *  Crustaceans – mobile species “keystone”  Sedentary species worms etc. record of recent past conditions  It’s Complicated – few simple effective tools

22. End