Effects of global warming on marine mammals
The effect of global warming on marine life and mammals is a growing concern. Many of the effects of global warming are currently unknown due to unpredictability, but many are becoming increasingly evident today. Some effects are very direct such as loss of habitat, temperature stress, and exposure to severe weather. Other effects are more indirect, such as changes in host pathogen associations, changes in body condition because of predator–prey interaction, changes in exposure to toxins and CO2 emissions, and increased human interactions. Marine mammals that have been affected by climate change include walruses, seals, polar bears and many more.
Marine mammals have evolved to live in oceans, but climate change is affecting their natural habitat. Some species may not adapt fast enough, which might lead to their extinction.
Ocean Warming Temperatures
During the last century, the global average land and sea surface temperature has increased due to an increased greenhouse effect from human activities. Warming has even reached depths of more than 700 meters (30% of ocean warming over the past decade has occurred in the deeper oceans below 700 meters). Many marine mammal species require specific temperature ranges to survive. Ocean warming will therefore lead to increased species migration, as endangered species look for a more suitable habitat. If a species cannot successfully migrate to a suitable environment, unless it learns to adapt to rising ocean temperatures, it will face extinction. Sea level rise is also important when assessing the impacts of global warming on marine mammals, since it affects coastal environments that marine mammals species rely.
Changes in temperatures change the location of areas with high primary productivity. Primary producers, such as plankton, are the main food source for marine mammals such as some whales. Species migration will therefore be directly affected by locations of high primary productivity. Water temperature changes also affect ocean turbulence, which has a major impact on the dispersion of plankton and other primary producers. Due to global warming and increased glacier melt, Thermohaline circulation patterns may be altered by increasing amounts of freshwater released into oceans and, therefore, changing ocean salinity. Thermohaline circulation is responsible for bringing up cold, nutrient-rich water from the depths of the ocean, a process known as upwelling
Specific marine life and mammals being impacted
Polar bears are one of the marine mammals that are most at risk due to climate change. The biggest issue for polar bears related to climate change is the melting of ice as a result of increasing temperatures. When the ice melts, polar bears lose their habitat and food sources. Although polar bears have been known to eat more than 80 species of animals, most of their diet consists of seals, which are also endangered by global warming. There have been an increasing number of polar bear drownings because they become exhausted by having to swim farther to find ice or prey.
Not only are marine mammals impacted by climate change but so is other marine life. An example of this could be Coral. When coral is introduced to warming ocean temperatures changes, runoff and pollution, overexposure to sunlight extremely low tides and other stresses, the coral will expel an algae growing on them. They have a symbiotic relationship with the algae. When the coral expels the algae it becomes bleached or "completely white". This is called Coral Bleaching. The coral then become more vulnerable to disease and death. Coral reefs make up a large part of our oceans ecosystems that are teaming with life. One of the main homes of coral are in coral reefs. Climate change has caused a synergy between ocean acidification, ocean warming temperatures, and expansions of the oxygen minimum zone that will increase a sensitivity and vulnerability, that will move coral reef resources toward extinction.
- Burek, Kathy A.; Gulland, Frances M. D.; O'Hara, Todd M. (2008). "Effects of Climate Change on Arctic Marine Mammal Health" (PDF). Ecological Applications. 18 (2): S126–S134. doi:10.1890/06-0553.1. ISSN 1051-0761. JSTOR 40062160. PMID 18494366.
- Trathan, Phil N.; García-Borboroglu, Pablo; Boersma, Dee; Bost, Charles-André; Crawford, Robert J. M.; Crossin, Glenn T.; Cuthbert, Richard J.; Dann, Peter; Davis, Lloyd Spencer; De La Puente, Santiago; Ellenberg, Ursula; Lynch, Heather J.; Mattern, Thomas; Pütz, Klemens; Seddon, Philip J.; Trivelpiece, Wayne; Wienecke, Barbara (1 February 2015). "Pollution, habitat loss, fishing, and climate change as critical threats to penguins" (PDF). Conservation Biology. 29 (1): 31–41. doi:10.1111/cobi.12349. ISSN 1523-1739. PMID 25102756.
- Harwood, John (1 August 2001). "Marine mammals and their environment in the twenty-first century". Journal of Mammalogy. 82 (3): 630–640. doi:10.1644/1545-1542(2001)082<0630:MMATEI>2.0.CO;2. ISSN 0022-2372.
- Simmonds, Mark P.; Isaac, Stephen J. (5 March 2007). "The impacts of climate change on marine mammals: early signs of significant problems". Oryx. 41 (1): 19–26. doi:10.1017/s0030605307001524.
- Tynan, Cynthia T.; DeMaster, Douglas P. (1997). "Observations and Predictions of Arctic Climatic Change: Potential Effects on Marine Mammals" (PDF). Arctic. 50 (4): 308–322. doi:10.14430/arctic1113.
Animals have a high risk of mortality.
- Learmonth, JA; Macleod, CD; Santos, MB; Pierce, GJ; Crick, HQP; Robinson, RA (2006). "Potential effects of climate change on marine mammals". In Gibson, RN; Atkinson, RJA; Gordon, JDM (eds.). Oceanography and marine biology an annual review. Volume 44. Boca Raton: Taylor & Francis. pp. 431–464. ISBN 9781420006391.
- Laidre, Kristin L.; Stirling, Ian; Lowry, Lloyd F.; Wiig, Øystein; Heide-Jørgensen, Mads Peter; Ferguson, Steven H. (January 1, 2008). "Quantifying the Sensitivity of Arctic Marine Mammals to Climate-Induced Habitat Change". Ecological Applications. 18 (2): S97–S125. doi:10.1890/06-0546.1. JSTOR 40062159. PMID 18494365.
- Map Shows Vast Regions of Ocean Are Warmer March 30, 2013 Scientific American
- Warming Ocean Threatens Sea Life; Warming down to 700 meters could also affect currents, weather March 30, 2013 Scientific American
- New Research Confirms Global Warming Has Accelerated March 25, 2013 Skeptical Science
- Balmaseda, Magdalena A. (2013). "Distinctive climate signals in reanalysis of global ocean heat content". Geophysical Research Letters. 40 (9): 1754–1759. Bibcode:2013GeoRL..40.1754B. doi:10.1002/grl.50382.
- Glick, Patrick; Clough, Jonathan; Nunley, Brad. "Sea-Level Rise and Coastal Habitats in the Chesapeake Bay Region" (PDF). National Wildlife Federation. Retrieved November 8, 2014.
- Sarmento, H.; Montoya, JM.; Vázquez-Domínguez, E.; Vaqué, D.; Gasol, JM. (2010). "Warming effects on marine microbial food web processes: how far can we go when it comes to predictions?". Philosophical Transactions of the Royal Society B: Biological Sciences. 365 (1549): 2137–2149. doi:10.1098/rstb.2010.0045. PMC 2880134. PMID 20513721.
- Vázquez-Domínguez, E.; Vaqué, D.; Gasol, JM. (2007). "Ocean warming enhances respiration and carbon demand of coastal microbial plankton". Global Change Biology. 13 (7): 1327–1334. Bibcode:2007GCBio..13.1327V. doi:10.1111/j.1365-2486.2007.01377.x. hdl:10261/15731.
- Vázquez-Domínguez, E.; Vaqué, D.; Gasol, JM. (2012). "Temperature effects on the heterotrophic bacteria, heterotrophic nanoflagellates, and microbial top predators of NW Mediterranean". Aquatic Microbial Ecology. 67 (2): 107–121. doi:10.3354/ame01583.
- Mazuecos, E.; Arístegui, J.; Vázquez-Domínguez, E.; Ortega-Retuerta, E.; Gasol, JM.; Reche, I. (2012). "Temperature control of microbial respiration and growth efficiency in the mesopelagic zone of the South Atlantic and Indian Oceans". Deep Sea Research Part I: Oceanographic Research Papers. 95 (2): 131–138. doi:10.3354/ame01583.
- Castilla, Juan Carlos. "Marine Ecosystems, Human Impacts on". Encyclopedia of Biodiversity (2 ed.). Academic Press. pp. 56–63.
- Haldar, Ishita. Global Warming: The Causes and Consequences. Readworthy. ISBN 9788193534571.
- Derocher, Andrew. Polar Bears: A Complete Guide to Their Biology and Behavior. Johns Hopkins University Press. p. 84.
- Parsons, Edward; Milmoe, B.J.; Rose, Naomi. "Polar Bears". Encyclopedia of Global Warming & Climate Change (2 ed.). SAGE Reference. p. 1114.
- US Department of Commerce, National Oceanic and Atmospheric Administration. "What is coral bleaching?". oceanservice.noaa.gov. Retrieved 2019-11-14.
- Páez-Osuna, F.; Sanchez-Cabeza, J. A.; Ruiz-Fernández, A. C.; Alonso-Rodríguez, R.; Piñón-Gimate, A.; Cardoso-Mohedano, J. G.; Flores-Verdugo, F. J.; Carballo, J. L.; Cisneros-Mata, M. A.; Álvarez-Borrego, S. (2016-11-01). "Environmental status of the Gulf of California: A review of responses to climate change and climate variability". Earth-Science Reviews. 162: 253–268. doi:10.1016/j.earscirev.2016.09.015. ISSN 0012-8252.
- Poloczanska, E. S., Babcock, R. C., Butler, A., Hobday, A. J., Hoegh-Guldberg, O., Kunz, T. J., Matear, R., Milton, D. A., Okey, T. A., & Richardson, A. J. 2007. "Climate change and Australian marine life". Oceanography and Marine Biology: An Annual Review, 45, 407–478.
- Marine Climate Change Impacts Partnership. 2006. "Marine Climate Change Impacts Annual Report Card 2006". (Eds. Buckley, P.J., Dye, S.R., & Baxter, J.M..), Summary Report, MCCIP, Lowestoft, 8pp.