On today’s episode of Ocean Talk Friday, Andrew and I live-blabbed about three various stories in the news affecting our ocean ecosystems. Going forward, feel free to tune into our discussions on Blab live Wednesday nights!
- Sharks Smell Well – New research out of Scripps claims that leopard sharks use olfactory cues to navigate throughout the open ocean. In environments devoid of many visible landmarks and reference points, many migratory animals (like sharks) need to utilize some other sense to navigate their way through the big blue. The authors of this study observed that when sharks have their sense of smell impaired, they are much less likely to swim in a straight distance to a single location; rather, they swim in frenzied patterns indicative of an animal that has lot its sense of direction. Though this study looked strictly at leopard sharks, it’s thought that other shark species use olfactory cues as well for underwater navigation. This type of information can be quite relevant when developing policies against marine pollution or other chemical dumping that may influence the chemistry of the ecosystem, since chemical changes could disrupt olfactory recognition and navigational ability of vital shark species.
- Sea Cucumbers in Trouble – An article from Al Jazeera America depicted an unusual fishery dispute in the Banana Islands, just off the coast of Sierra Leone. Though the story has all the usual characters of overfishing situations (local communities practicing subsistence fishing while foreign industrial business folks bring in new technology to overharvest the local marine resources), it does have one unique twist: this is a sea cucumber fishery. While not a large industry in North America, sea cucumbers are very popular in east Asian recipes and traditional medicine. Unfortunately, this demand has led to an overexploitation of the Banana Island population. It has also made it more difficult for the local fishers to support themselves, as catches get lower and the price per individual drops as well. Hopefully we’ll start to see the local government take a stand and reduce catch quotas or these productive, coastal habitats may lose a vital component of their ecosystem.
- What do Whales do at Night? – The nighttime behavior of multiple whale species has been a question facing marine researchers for decades. Since most of our observational techniques for discerning marine mammal behaviors relies on light, it has been near impossible to gather any meaningful information about the nighttime behavior of right whales and blue whales. However, recently acoustic methods and infared technology have been used to observe these marine mammals in the absence of light. This data suggests that different whale species behave differently when the sun goes down; blue whales, for example, tend to relax near the surface of the water. This may be one of the reasons why this species is so vulnerable to ship strikes. The animals themselves aren’t moving around much, and neither the whale nor the boat has the visible capability to stop the collision. Right whales, on the other hand, appear to use the night to feed on plankton at deep depths. These advancements in technology should provide many more insightful discoveries into the daily life of the largest animals on earth.
Enjoy the Podcast!