They need to attach themselves to the gills of a host fish within a couple days. Most freshwater mussels team up with only one type of fish. Our northwest species favor salmon and without salmon as hosts, mussels cannot successfully reproduce. Once the larval mussels attach to the fish, the fish body reacts to cover them with cells—an unconscious action that forms a cyst, where the glochidia remain for two to five weeks depending on the temperature. Hitchhiking on a fish is a baby mussel's only opportunity to travel and experience more of the world, and traveling this way results in a free ride to a new home.
After the mussels change from the larval form and begin to resemble adults, they break out of the cyst and fall to the bottom of the stream where they bury themselves in the bottom and begin to live an independent life.
Only one in a million survive to the adult stage, but to offset these low odds, mussels lead a very long reproductive life and produce millions of eggs per year! Although one would expect to see mussels in most of our streams and rivers, they often aren't there.
They are only found in the cleanest streams and rivers with cool, clear water and bottoms that aren't muddy. Western pearlshell Margaritifera falcata live in rivers and streams with cool, flowing water. The most common mussel in our area is M. An identification tip: most Margaritifera falcata have purple color on the inside of their shell and other local mussels do not. Oregon floaters Anodonta oregonensis are found in slower moving water. One obvious difference between freshwater and marine mussels is that freshwater mussels live in freshwater streams, rivers, ponds and lakes while marine mussels live in salt water oceans and bays.
Marine mussels taste wonderful in a garlic butter or marinara sauce while freshwater mussels taste like an old dirty shoe. Most freshwater mussels in New Jersey also have a protected status and cannot be harvested or collected. Even possessing the shell of an endangered or threatened species is illegal without a permit.
Although unpalatable to humans, freshwater mussels are prey for raccoons, otters, and crayfish. Marine mussels are prey for some birds, sea stars, and some marine snails. Marine mussels reproduce by releasing their eggs and sperm into the water. The young then begin life as floating plankton for between one and six months before settling on the bottom as an adult. With freshwater mussels, the male releases sperm into the water which then enters the female via her incurrent siphon.
After feeding on the fish during their larval stage, they detach themselves, fall to the bottom, and begin their adult stage. Most marine mussels and the invasive freshwater Zebra mussel; which is not within either the Palaeoheterodonta or Pteriomorphia subclasses use threads calls byssus to attach themselves to underwater rocks, jetties, and other structures.
Freshwater mussels are more mobile, using their powerful foot to move along the substrate and bury themselves. After fertilization, the eggs develop into a larval stage called glochidia. In a variety of species-specific methods, these tiny worm-like glochidia get transferred to the bodies of larger fish which are foraging for a meal.
For example, the Fragile Papershell mussel needs freshwater drum to complete its reproductive cycle, while the Rainbow mussel must pair up with smallmouth bass, largemouth bass, spotted bass or rock bass. Utilizing swimming fish as part of their reproductive process also allows mussels to disperse their offspring over a much wider range than could be accomplished otherwise. Today, nearly two-thirds of Ozarks mussel species are classified as species of conservation concern. This fact should raise human concern because mussels benefit humans through their feeding process.
Their filter feeding helps keep water clean.
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