Thermoregulation der Florida Manatis (Trichechus manatus latirostris) - Untersuchung zum Verständnis des Kältestresssyndroms (Cold-Stress Syndrome) im Hinblick auf physiologische Grundlagen, Morphologie und Früherkennung
Ökologie und Biodiversität der Tiere und Ökosysteme, Organismische Interaktionen
Zusammenfassung der Projektergebnisse
This project aimed at the investigation of thermoregulation in Florida manatees with emphasis on cold stress, which is, along with boat strikes and harmful algae blooms (HABs), one of the major threats to Florida manatees. These herbivorous marine mammals are highly adapted to a warm environment; however, winter temperatures have been decreasing in South Florida in the course of climate change. Despite continuously increasing threats by increasing boat traffic, increasing number, intensity and duration of HABs, decreasing winter temperatures, and decreasing availability of warm water refuges, the Florida manatee was recently reclassified from Endangered to Threatened under the Endangered Species Act of 1973. The more important is enhancing knowledge about causes, prevention, early indicators, and treatment of cold stress in manatees. Up to now there has been no reliable non-invasive method to measure body temperature in a manatee. We found indication that temperature of the nasal mucosa within the nostrils of Florida manatees, measured by means of infrared thermography (IRT) during a breath, displays relative changes in body temperature over time. This approach provides a simple non-invasive method to monitor the thermal state of a manatee during sedation, transportation, health assessments and other potentially stressful situations. IR based temperature measurement of the nasal mucosa is likely to be applicable not only in manatees, but in other species as well, such as in captive predators or great apes, which is of great interest for veterinarians and animal care staff. Long-term measurements of skin temperature revealed astounding consistency and congruency of spatial temperature patterns in two Florida manatees. Spatial temperature distribution across the 25 measuring sites on the entire body was not only steady intraindividually over the course of two years, but congruent in both manatees. This static heat flux pattern is in line with manatees’ limited abilities to actively regulate peripheral circulation. However, considering the temperature differences of less than 1°C between measuring sites, this precise and consistent pattern is the more intriguing and sheds new light on heat dissipation in manatees. Further projects, such as the development of “floating greenhouses” providing manatees with warm air in winter, are still in progress, which will likely serve prevention, early recognition and treatment of cold stress in Florida manatees, thereby supporting conservation efforts for this fascinating species. Media coverage: https://mote.org/news/article/manatee-temperature-study-could-advance-rehabilitative-care http://www.jacksonville.com/news/20180328/sarasotas-mote-marine-develops-new-way-tomonitor-manatees-temperatures https://www.youtube.com/watch?v=LioZrrYFIkU https://mote.org/podcasts/item/taking-a-manatees-temperature-trickier-than-it-sounds
Projektbezogene Publikationen (Auswahl)
- Analysis of nostril temperature and breaths as a diagnostic tool in Florida manatees. 22nd Biennial Conference on the Biology of Marine Mammals, Halifax, Canada, Oct. 2017
Erdsack N., Ball R., Reynolds J. E. III
- Heat flux in manatees: A new approach to estimate metabolic rates in Florida Manatees (Trichechus manatus latirostris). 110th Annual Meeting of the German Zoological Society (DZG), Bielefeld, Germany, Sept. 2017
Erdsack N., McCully-Phillips S. R., Rommel S. A., Pabst D. A., McLellan W. A., Reynolds J. E. III
- Serial visual reversal learning in harbor seals. The 24th International Conference on Comparative Cognition, Melbourne Beach, FL, USA, Apr. 2017
Erdsack N., Dehnhardt G., Hanke F.D.
- (2018). Heat flux in manatees: An individual matter and a novel approach to assess and monitor the thermal state of Florida Manatees (Trichechus manatus latirostris). Journal of Comparative Physiology B 188 (4):717-727
Erdsack N., McCully Phillips S. R., Rommel S. A., Pabst D. A., McLellan W. A., Reynolds J. E. III
(Siehe online unter https://doi.org/10.1007/s00360-018-1152-7) - Nostril temperature as indicator for body temperature – Using infrared thermography as a diagnostic tool in Florida manatees. Florida Marine Mammal Health Conference VI, Orlando, FL, USA, March 2018
Erdsack N., Ball R., Reynolds J. E. III
