Abstract

In mid January 2010, the state of Florida experienced a massive sea turtle cold stunning event. Thousands of sea turtle species stranded either on beaches or were found floating in bays and coastal areas where water temperatures fell below 50 degrees Fahrenheit. The cold stun event affected the East Coast Atlantic waters earlier with the Gulf Waters and Panhandle area a short time later. Sea turtles were rescued and transported throughout the state to facilities that had capabilities to triage and provide warm water. Most sea turtles rescued were of juvenile age classes in four of the five native species to Floridian waters. Green sea turtles were the largest group affected. Both non fibropapilloma (non FP) and fibropapilloma (FP) green sea turtles were represented in the rescued numbers. Fibropapilloma tumor growth varied from scant to moderate growth on the sea turtles admitted to CMA.

Clearwater Marine Aquarium (CMA) responded to 105 cold stun sea turtles from January 6^th through January 17^th, 2010. These animals were transported from the East Coast and within Pinellas County with initial body temperatures ranging from 48 degrees F to 60 degrees F. Visually most of the sea turtles presented in fair to good body condition. As part of a triage protocol, full blood chemistries and complete blood counts (CBCs) were taken on many animals. Blood was sent to Antech Laboratories for Avian /Reptilian CBC and Chemistry panels. P CBC variables included hematocrit, leukocytes, absolute lymphocytes, neutrophils (heterophils), monocytes, basophils, eosinophils and azurophilic monocytes. Parameters on the Reptilian chemistry panel included glucose, globulin, albumin, calcium, sodium, chloride, potassium, phosphorus, CPK, AST, uric acid, total protein and BUN. Since this cold stun event was an acute solitary event, it was unknown if the effects seen on the turtles behavior would be reflected in the primary blood results. FP green sea turtle blood values upon admittance to CMA did not seem to vary significantly from non cold stun green sea turtles. Plasma chemistries were similar and though low glucose was anticipated, blood glucose levels were in the middle range for foraging, healthy green sea turtles. For example, mean values for glucose were 109 mg/dL (n=12, STDEV=19.93) for the CMA cold stun group and 113.5 mg/dL (n=8, STDEV= 48.51) for the non cold stun group. Calcium values were slightly below normal range for 87% (n=12, mean 5.8 mg/dL, STDEV=1.03) of the FP green sea turtles and differed from the non cold stun green sea turtles 6.36mg/dL (n=8, STDEV=1.45). Decreases in calcium levels have been reported in other hypothermic reptiles such as cold stunned Kemps Ridley sea turtles (Lepidochelys kempii).¹

Based on what we know about cold stun events, healthy turtles get caught in bays where the coastal and upper water column temperatures drop below a metabolic safety zone and these sea turtles go into a sort of suspension of animation, both physically and systemically. Turtles recovered during the early phase of an acute cold stun event may not show significant changes in blood parameters. Pathologic shifts may occur later in the rehabilitation process, so any turtle showing persistent lethargy, poor appetite or lack of swimming when stimulated should be rechecked for changes in the bloodwork that may indicate secondary issues such as pneumonia. Blood parameters seemed to verify that the best approach in the early phase of an acute cold stun events is to warm the animals as soon as possible and to be aware that these parameters may differ a few days later or in turtles arriving later in the event.

Reference

1.  Innis CJ, Tlusty M, Merigo C, Weber ES 2007. Metabolic and respiratory status of cold-stunned Kemp's Ridley sea turtles (Lepidochelys kempii). J Comp Physiol B 177:623-630.