For the past few days I have been getting a lot of pictures sent to us with the same question. What in the heck are these freaky looking things. Some of the questions were much more descriptive and colorful. Fast swimming worms swarming around boats and people not wanting to get near them. Do they bite was another popular question. First off, no, they do not bite. Secondly, these are cinder worms (Nereis limbata) also known as May worms and this is a spawning ritual or hatch. Usually these spawns occur during a full moon and we are in that cycle right now with the sturgeon moon. Sediment and water temperature also play a role in these spawns, and our waters have been flip-flopping temperatures the entire summer.
Normally cinder worms live in the mud, and are mud burrowing worms, but when it is time to reproduce they grow a paddle tail. Then they detach from their body releasing all the segments except the one that contains the reproductive cells. Now they can swim, the swarm begins and they move to the surface of the water. Releasing their sperm and eggs in an all out frenzy. That is why they swim fast and erratic. Usually this happens at night and they are attracted to light, but spawns do occur during the afternoon. This is not really a hatch but a spawning, but since they resemble insects when they emerge or hatch the description has stuck.
Fish go crazy for these swarms and will feed heavily on the cinder worms, especially striped bass. The hard part is fishing this swarm because all the fish want to eat are these worms and you can’t just grab one and put it on a hook they will break apart. This is only a small part of the entire worm at this point. You can match the hatch so to speak with four-inch pink sluggos, or try pink zooms. Soft plastics will be your best bet of the same color for sure. Moving water will induce more strikes and increase your chances. Fish will be hitting individual worms, you will have to anticipate a the fish’s path to get in the strike zone. During the full moon cycles when this spawn occurs you can use these soft plastics to increase your chances of catching striped bass. You best bet will be with fly fishing gear to match this hatch. It is difficult to do this with spinning gear, but it can happen. Move your plastics around with fast erratic action like the worms you see in this video. If you are in slow-moving water move the lure slower. Bass will be slurping these worms by the handful in slower water. Again you will have to anticipate the fish’s next move to get your lure in their face. It is easy to fish a spawn, just hard to catch