Shark Podcasts

The weekly podcasts deal with an array of questions revolving around sharks. A critical look is given from the viewpoint of an experimental shark behaviorist, conservationist, and professional educator to all aspects around them.

Episode 50: "Yawning," a common but rather unknown maintenance behavior among sharks

Whenever a shark gouges, its upper jaw is everted to get an optimized grip onto the targeted object. During retraction it can happen that the tendons and ligaments–connecting the upper jaw with the brain capsule–are not properly repositioned, leading to a very much slowed down simulated biting act, called "yawning," to enhance the probability of a correct repositioning. Different, interesting aspects are discussed and highlighted.

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Episode 49: On experience within ADORE-SANE

Within the shark-human interaction concept there are two forms of experience (E), one is the experience with the actual activity (A), the other is the one with sharks, theoretically and practically. Both forms of the latter are helpful, as long as one remains critical how to use them. Here, we talk about the pros and cons of experience, how to weigh it but also where to be critical. We also briefly touch the issue of how to choose an operator since they are most often closely connected to a diver's practical experience.

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Episode 48: On chafing

Sharksuckers often irritate sharks when attached to them, hence the sharks try to either get rid of them or at least force these teleosts to reposition themselves to other less irritating spots on the shark's body. A seemingly prerequisite for a successful attempt by the shark to relocate a sharksucker or get rid of it alltogether is body awareness. Beside the latter, we talk about the different ways a shark tries to get rid of a sharksucker and what it entails, as well as the potential advantage of having those sharksuckers attached.

Episode 47: Who is really responsible for the "JAWS effect"

When talking about the devastation of sharks, the movie "JAWS" is mostly made responsible. But if the author of the book or the producer of the movie are to blame–which should not be the case–, another group of men needed to be mentioned: the shark scientists of that time. Their lack of inwater experience with sharks, due to their own fear of them, prevented these scientists from understanding a shark's true behavior, thus recommendations and suggestions of how to behave should one have to face a shark were not just ridiculous but even dangerous.

Episode 46: On the destruction of food chains

A basic marine food chain starts with phytoplankton as the lowest level, followed above by zoo planktion, then filter feeding fish and predators/top predators, with super predators at the top. Are the top layers removed or at least decimated to the point that they can not control their lower level (their food source) anymore, that level can grow exponentially what leads to an elimination of their food base, and so on. Sharks, as the most abundant top predators over 100 lbs or 50 kg are the most crucial representatives at the top of most marine food chains. Should the overfishing of sharks contine in such a magnitude, the desctruction of most marine ecosystems will follow.

Episode 45: On gliding and energy saving in sharks

Most of the known shark species can sometimes be observed gliding through the water. Gliding is presumed to preserve energy. But energy saving in sharks can also be accomplished by laying on the bottom. Such, however, needs strong gill muscles to force enough water over the gills.

Episode 44: "Tag & Release" is wrong

For many years, sportfishermen where asked by scientisits to catch sharks, tag them and let them go again, to get data should the same shark be caught again. This practice should not be allowed anymore. It is cruel to reel in a shark for the sake of giving it a tag. Even more so, since the shark has to be caught for a second time to get actual data from the animal. But even then, the gained data is poor and mostly inaccurate. The only justification for this type of procedure is using satellite tags, but even then, the past showed that not much has been done with that data either.

Episode 43: Bite rates in Florida

When it comes to shark bites, Florida has worldwide the most bites each year. However, in early years, the interpretation of these bite numbers were hardly ever satisfying since all that was done was to pinpoint where it happened and how many times. Due to this shortcoming, we introduced SatScan, a spatial scan statistical tool to get a better idea what really goes on. In addition to, we introduced 'bite rate,' a ratio between number of bites per area to number of people at this particular beach. Of course, the latter was not always easy to get, but most data stemmed from the United States Lifesaving Associations who collects so called 'beach attendances.' Where no number was available like non-populated shores with minimal activity, we had to use adjacent beaches to get a proxy. These results are the first of its kind. They give a much more solid idea of what really happens at the East coast of Florida.

Episode 42: It matters how you position yourself when facing a shark

Our research clearly showed that a shark stays farther away (significantly) from a person if he/she is in a vertical position instead of a horizontal one. Due to that, we propose that whenever you are facing a shark to get into a vertical position. Should the water be too deep to stand, let your feet dangle, and only move with your arms to keep position, and to pivot around your body axis to follow the shark with your eyes. This show dissects the vertical position and its advantages over the horizontal one.

Episode 41: Sharks and their emotions

Sharks have often been called (purely) instinct driven creatures. This implies that thery have no emotions. But can that truly be? Even more so, since even people who deny emotions in sharks, agree that shark are "aggressive" or "frustrated." Well, both of them, are emotions. Being in the water with sharks all the time showed me, over and over, that this animal must possess emotions. There is no reason to assume that sharks do not have them. Although we never know what a shark truly thinks, we can at least be open enough about it. Look a shark in the eye the next time you see one and assume that there are no emotions. It won't work.