The Next 4-7 Years of My Life of Working in the Greater Everglades—Will It All Be Lost to Sea Level Rise?

Pine Rockland post-fire
Big Pine Key, FL

     As I start the first field season of my dissertation research, I am starting to get the sensation that I have jumped onto a sinking ship¹. My chosen ecological system, the pine rocklands (see photo Big Pine Key), has a laundry list of complex and entangled threats—invasions of plant and insect species, habitat fragmentation, climate change, hurricanes, floods, fire suppression, and of course, since it is only found only within south Florida and Caribbean islands, sea level rise (SLR).

         

    

 

       

The majority of my research does not directly incorporate SLR into the hypotheses, but rather focuses on examining landscape patterns and metacommunity dynamics that will help guide conservation and management practices. Yet, I still find myself concerned with the long-term persistence of the endemic and/or endangered species (48 plants and 5 animal species) that rely on this habitat. It has been well documented that low-elevation islands and coastal regions worldwide face the imminent threat of a 1-meter rise in sea-level by 2100^1,2,3 accompanied with increases in storm surge frequencies and magnitude. With these facts in mine, the majority of my research sites will either be under water or dealing with salt water surges or intrusion by that point—so I have to ask, what will happen to all my precious plants and insects that I am so passionately devoted to understanding and conserving?

Key Deer in Pine Rockland on Big Pine Key, FL

Remaining Habitat in Keys after 1-m sea level rise
(adapted  Figure 1 Mashinski et al. 2011)

            Four species, Big Pine partridge pea (Chamacrista lineata var. keyensis), sand flax (Linum arenicola), Key deer (Oedocoileus virginianus clavium) (see photo) and Lower Keys marsh rabbits (Sylvilagus palustric herneri), have already been identified to be species of great conservation concern since only 10% of their habitat will remain after the projected 1 meter SLR occurs (see adapted Fig. 1 from Mashinski et al 2011).  Areas of Bine Pine Key have already demonstrated loss of pine rockland communities due to storm surges and salt water intrusion (see photo of dead pine tree snags with an understory of salt-marsh and mangrove species). But it isn’t just the species of the pine rocklands at risk. Sans the few species that are highly tolerant of salinity, the entire south Florida community—plants, animals, humans, and all—will have only three options: emigrate, adapt, or perish.

Slash Pine Dead Snags in Background, Green Button Wood
Salt Marsh Understory
Big Pine Key, FL

            So, what if anything should we do about it? In Florida, where it is well known that our fair state was over twice its size 20,000 years ago and shrunk due to SLR at the end of the last ice ageto a size smaller than today⁴, what is the most appropriate  answer? Should we prioritize studying and preserving only the species that have potential to emigrate or adapt? Should we prepare for assisted migrations of species that would otherwise be lost? If we do that, what about the species that reside in current inland areas, will these migrations displace them? Should we look for phenotypes of species that have high saline tolerance and genetically engineer salt-tolerant species? While I do not know the answers to these questions, I do know that we need to diversify our approaches in order to prepare for environmental stochasticity and continue to establish long-term data resources. However, we need to establish these projects not only coastal systems, but in the upland and inland systems connected to these coastal communities, as these sites will be where many species will migrate. Otherwise, how else will we know be able to verify that these truly unique events are “abnormal” or extreme or how these events will be reshape communities at a landscape level? So, what am I going to do about it? Well, while the pine rocklands are still above water, I’m going to try to better understand the local patch and regional dispersal events, in case we lose some of them along the way.

-Julia Gehring

Citations:

1) Maschinski J, Ross MS, Liu H, O’brien J, von Wettberg EJ, Haskins KE. "Sinking ships: conservation options for endemic taxa threatened by sea level rise." Climatic change 107.1-2 (2011): 147-167.

2). Overpeck JT and Weiss JL. “Projections of future see level becoming more dire. PNAS 106(2009):21461-21462

3) Donoghue JF. Sea level history of the northern Gulf of Mexico coast and sea level rise scenarios for the near future. Clim Change 107(2011).

4). Allen G and Main MB. “Florida Geological History.” Univeristy of Florida IFAS Extension Office. Pub # WEC189. < http://edis.ifas.ufl.edu/uw208>