Sea Lamprey



There are many interesting anatomical features of sea lampreys. They are eel like in shape, with 7 gill openings and an inconspicuous median fin. This median fin becomes quite pronounced in the males as they ascend the river in breeding condition. Though the lamprey's eyes are small they are certainly functional. There is a third, pineal, eye located on top of the head which functions to regulate circadian rhythms. The entire skeleton is made of cartilage. The spinal cord is supported by a notochord, rather than surrounded by a bony vertebral column. Sexually mature adults average 2 to 2.5 feet in length..

The anadromous life history strategy involves breeding in fresh waters and migrating to the sea. At some point the seagoing adults return to the natal streams to breed. Lamprey, like many anadromous fishes, are selmelparous, they come upstream once to spawn then they die. The adults start moving up the river in late March and early April.

PRCWA Contacts

We'd love to hear from you and get your input on ways to preserve the Parker River Watershed and the Plum Island Sound.

PO Box 798, Byfield, MA  01922
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Webmaster: Jerry A. Mullins

 Contribute to our Online Watershed Journal!

Share common experiences & observations in our three beautiful watersheds (Essex, Ipswich, Parker).  Please share your activities with your photographs, mapping your location, and if possible, a journal reflection.


The results of your journal entry will be visualized, along with all of the other participants.

Our Purpose!


The PRCWA is a community-based, non-profit organization dedicated to promoting the restoration and protection of the waters and environment of the Parker River and Plum Island Sound Watersheds.


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Help us spread the word about the importance of protecting our pristine  Parker River Watershed for the benefit of our quality of life and for the preservation of our environment .

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