This article will give you an idea of how shrimp live and why they come to our areas each year. It will also help explain why there are only a few shrimp one week and buckets full the next.
Biological / Migratory Cycles of Penaeid Shrimp
The species of shrimp that are most commonly caught near shore in Florida are called Penaied Shrimp. There are many different varieties of shrimp in the world and these just happen to be the type that live near here. Penaied shrimp are also one of the prime shrimp species that inhabit the entire Gulf Coast region and are the main harvest pulled in by the Texas and Louisiana shrimping fleets.
Penaied shrimp go through several stages and environments in their development. The first stage in a shrimp's development, like almost all life on earth is that of an egg. Shrimp eggs, laid in deep water, are very small and sink to the bottom during spawning or are carried off into current. Many of the eggs are eaten by predators, crabs or other sea life. Those that survive mature into Nauplius and subsequently, Protozoea. These initial three stages are invisible to us shrimpers as they occur offshore in deep water.
The stage following Protozoea is known as Mysis. During this period in a shrimp's development cycle, shrimp begin to make their way closer to shore and to estuaries in order to receive protection from ocean dwelling predators. Depending on how close your shrimping location is to the open water, you may begin to see them in the grass flats as microscopic glowing orange dots. At first, you may be tempted to think that they are full size shrimp but this is just an optical illusion. When you lower an Ozello Shrimper on top of them, they slip right through the holes. About the size of a very small pebble, they wouldn't be very much to eat anyway.
Shrimp change from Mysis to Postlarvae during their migration into the estuaries. It is during this period in time that the shrimp need the most protection as they are now visually on the radar of a much wider range of predators than they were as microscopic creatures. The estuaries, filled with grass, low tides, and plenty of sand to hide in, provides just such a protection. It also provides an area that is stable and not subject to a high level of wave action or moving currents. As they mature into Juveniles, and depending on the size and geography of the estuary, the shrimp may even move into fresh water sources such as rivers or streams.
Juveniles remain in the estuary and mature into Sub-Adults and Adults before they migrate back into the deep water to spawn or, lay they eggs. The West Coast Florida "shrimping season" as it has come to be called, is the period of time immediately before the shrimp gather together and make their journey back into the open ocean to reproduce. This period is when all of the shrimp gather as close together as they can to the open water, along channels, bridges, grass flats and other areas of easy access and high water flow in order to prepare for their departure. This also explains why shrimp appear in numbers and then, as if they were beamed up from space, all disappear.
A common misconception is that shrimp come close to shore in order to reproduce. The fact is, they have been there for quite some time. Most of them have been in the area for months, growing and waiting for their reproductive migratory cycle to begin. They head out to sea in order to lay their eggs; they do not come into shore to do so.
Another misconception is that shrimp can only be found in a few places. Nothing could be further from the truth. The only requirements for finding shrimp are understanding their migratory cycle, finding a tide that enables you to get out there, and going to a place where shrimp are queuing up to leave. It doesn't have to be close to the Gulf of Mexico at all. There are numerous reports of people catching shrimp far into Tampa Bay or in rivers along the coast. Anywhere near an estuary is a good place to look.
The last misconception is that there is only one good time to go out and that one good time is during a certain time of year. Sure, warmer water historically does better on the West Coast of Florida but that is only because the tides line up right and people actually are willing to go into semi-warm water. Shrimp "run" (into deep water) in the winter too but most people wouldn't be caught dead in sub 70 degree water.
Shrimping isn't a science but it helps to know a little. Like fishing, the more thought you put into it, the luckier you will be. Rumor, hearsay and other myths of shrimping are all around. Some people believe that if pink shrimp appear before red, the season will be good. Take what you hear with a grain of salt and then compare it to the facts. The truth of the matter is that no matter what happens, the shrimp are fairly predictable and knowing how they behave will leave you with a freezer full at the end of the "season."
Happy Shrimping Everyone, I hope this helps you and yours...