best resource for understanding migration
Can anyone direct me towards a good book or website that really nails the nuances of striped bass migration? I understand the general north/south pattern, but I am particularly interested in how "resident" populations fit into it all. For example, I live near the Schuylkill River, a tidal freshwater tributary of the Delaware River. I have caught numerous striped bass fry through the fall. Will they stay in the river through the winter? Do larger fish stay in the river as well? Do migrating stripers from Maine go back into these freshwater locales for stopovers on their way south? Thanks for any info.
Stripers spawn in fresh water and the young fry develop there for several months. They eventually move into brackish and saltwater environments where they will stay (through the winter) until they are two to four years old when they join the migratory group. Sometimes these young fish are referred to as resident fish, but most are only resident till they reach sufficient size to become migratory.
Some very large stripers may become resident fish and stay in the saltwater environment near the river from which they were spawned. Fish over 48 inches are caught in the middle of the summer some years, a time when most of the species have migrated north. Also, some stripers may be resident one year and then be a migrator the following year. Most likely it is food abundance and availability of cool water pockets that determine if that fish decides to stay for the summer.
Once a young striper leaves fresh water, it never returns until it is of sufficient age to make a spring spawning run up to the river in which it was born (natal river).