A scientific study, conducted by chilean and foreign researchers, determined that an increase in ocean temperature would reduce the recovery of the seminal material in this species, considered a key economic resource for the Magallanes Region.
Lorenzo Palma, IDEAL Center. The study suggests that the extraction of male crabs can trigger changes in the mating dynamics of a population, considered a key resource for the Magellanes Region.
The Chilean King Crab (also called Spider Crab) is a resource of great economic and social importance for the Magallanes region. The closed season, from December until the end of June, is intended to protect the species’ ability to successfully reproduce. Harvesting takes place during the months of August and November, and fisheries regulation only allows taking the adult male crab.
A recent study published in the prestigious academic journal “The Royal Society Open Science” identified the importance of sufficiently cold water in the development of crab sperm. The research was led by scientists Katrin Pretterebner, Miguel Pardo, and Kurt Paschke from the Research Center – Dynamics of High Latitude Marine Ecosystems (IDEAL) of the Austral University of Chile (UACh). The principal objective was to identify the effect of temperature on the sperm recovery rate in seminal reserves after mating.
For this work, the scientists conducted experiments in which they subjected 20 crab specimens to two different temperatures: 9 and 12º Celsius. The principal results revealed that, at 9°C, seminal recovery reaches 40% after 30 days, while at 12°C, it reaches only 21%.
“This sperm shows distinct limitations, beyond which there can be a reproductive loss in the resource if male bias is used as a capture factor,” said researcher Katrin Pretterebner. Faced with future climate change scenarios, the crab that lives at 12°C in northern Patagonia could be at greater risk.
This study also suggests that the extraction (harvesting) of large males can bring about changes in the mating dynamics of a population, thus reducing overall reproductive success.
If there is a reduction in the male population, this could affect the frequency of encounters with females. The few available males mate more often and this can deplete their sperm stores beyond the crabs’ capacity to recover,” noted Dr. Pardo.
This research is particularly relevant in a context of the latest report by the Intergovernmental Panel on Climate Change (IPCC). The report indicates that, for example, in the year 2100 the temperature of the Pacific Ocean could rise by up to 3°C.
Given this possibility, scientists concluded that, in the face of future climate change scenarios, the crab that lives in waters at 12ºC in northern Patagonia (between the Los Ríos and Los Lagos regions) could be at increased risk. On the other hand, in high latitude waters recovery could be faster.