With the rapid change in weather patterns, barometric pressure has driven many species of fish into wild feeding habits. Usually ahead of a change in pressure, migratory fish begin an exciting feeding pattern. Several anglers who have managed to get out into the harbor and avoid the floating debris, have reported that they have caught more sharks than usual. Unless you are experienced at tail roping a shark, and carefully holding on to the leader dangling from the shark’s mouth, getting an exact measurement of your catch is an estimate, at best. An example, the size and weight of the blue shark, a very slender and long shark, is often mistaken for a shark of several hundred pounds by the angler. In fact, an eight-foot blue shark usually weighs around 135 pounds.
I have spent a great deal of time researching the factors of weight versus size in the shark population. I found a very interesting study published by the Apex Predators Program of NOAA’s National Marine Fisheries Service. This service collects shark tagging information from commercial and recreational anglers that includes shark identification, weight and length. The research team put together a chart of predicted weights in pounds based on the shark’s fork length. The fork length is the measurement from the tip of the shark’s nose to the base of the shark’s tail. To many anglers surprise, the five-hundred- pound shark (estimate made by the angler) is more like 150 lbs.
I have reported the fork length of several species of sharks at a length many anglers reported as the actual weight. I have selected the length of six feet to use in reporting actual weights from the data provided by the APEX PREDATOR PROGRAM. Below are some of the reported weights from the study.
○ Mako Shark 147 lbs.
○ Pointer Shark 138 lbs.
○ Dusky Shark 144 lbs.
○ Sand bar Shark 157 lbs.
○ Tiger Shark 132 lbs.
○ White Shark 159 lbs.
○ Hammerhead Shark 114 lbs.
Other studies have looked at the teeth of sharks and the rings of growth found in the vertebrae of sharks to help determine age and weight. For example. the legendary Megalodon, which died out about two to three million years ago, gave birth to a baby shark of six feet long, based on the measurement of its vertebrae and teeth. Other earlier species of sharks were determined, through teeth and vertebrae studies, to be substantially the same in length and weight as their modern variety. You will find in this article several pictures of modern and prehistoric teeth that have been used in weight and length studies. These specimens are from the collection of Jay and Sue Lev and have been used in research studies by many marine biologists. The teeth have been collected from species found off Montauk, Long Island; Aurora, North Carolina; Calvert Cliffs of Maryland; local beaches in Florida; and from the construction widening project of upper Burnt Store Road.
The range of sharks is worldwide and for the most part, research has shown a good basis for determining a real weight-to-length estimate. When catching a shark don’t lose the fun of estimating the length of the shark. A little fisherman’s white lie can lead to some great conversation. Always remember, you can find the true weight and possible length through some of the many outstanding research reported in the literature about the evolution of sharks.
Tight lines
These specimens are from the collection of Jay and Sue Lev and have been used in research studies by many marine biologists.
