A Springtime Tradition: Sea-Run Brook Trout
Open water fishing is just around the corner and before we all dash out the door on April 1 with rod in hand, I would like to talk to you about an interesting topic. Almost everyone knows that brook trout live in streams, ponds, rivers, and lakes. Did you know, however, that brook trout also thrive in the coastal estuaries and in the Gulf of Maine ? These fish are known as sea-run brook trout or “salters” and recently there has been an increased interest in them.
Brook trout in Maine’s coastal streams have a unique behavioral strategy known as anadromy. Anadromous brook trout are those that leave their freshwater juvenile habitats and enter salt water conditions for a portion of their life, then return to freshwater at some point to spawn. Not all brook trout in coastal streams enter the salt water. There are some trout that live, grow and spawn in freshwater. It is unknown why some individuals prefer to stay in freshwater and some choose to head to sea. Preliminary research has shown little evidence that genetic differences contribute to these behavioral differences. Salter trout do not have the same coloration as their freshwater brethren. Salters adopt a silver to steel blue sheen with a white belly. The red dots with blue halos fade away to leave just yellowish spots. Once the trout return to freshwater, the beautiful coloration of typical freshwater brook trout returns within a couple of weeks.
Sea-run trout move downstream into the ocean anywhere from April through June and return to freshwater sometime from May to early August. It is likely that sea going individuals continuously move in and out of the estuaries to forage or to seek better temperature conditions. There is a lot yet to learn about why some coastal brookies head to sea and some do not !
Historically sea-run brook trout ranged from New York’s Long Island to Labrador, Canada. Today their range is reduced from its original size, but populations in the U.S. persist in Massachusetts and Maine, and perhaps Rhode Island. Sea-run trout have never been intensively surveyed in Maine and their current distribution, population status and potential threats in Maine are uncertain.
In response to this lack of information, the Maine Department of Inland Fisheries and Wildlife started an effort to gather needed data on these unique populations. Our approach involves enlisting the assistance of volunteer anglers to collect data over a wide area of the state and report their angling effort, success, and fishing location to IF&W fisheries biologists. The volunteer angler surveys began in 2006 and will continue through 2008. At the end of the 2008 fishing season the data will be analyzed and used to help determine the future needs of IF&W and sea-run brook trout.
The data collected by anglers to date has been excellent, however IF&W is interested in increasing public participation in 2008. If you would like to participate in the volunteer angler surveys please contact IF&W Fisheries Research Section: Merry Gallagher at (207) 941-4381 or merry.gallagher@maine.gov
A collaborative research effort is under way on Mount Desert Island where a single population of sea-run brook trout in Stanley Brook is being closely studied and monitored. The partners in this effort include IF&W, the National Park Service, the University of Maine, and the Conte Anadromous Fish Research Laboratory in Turner Falls, MA. Stanley Brook, which is located in Acadia National Park, is approximately 1.2 miles long and drains directly into the Gulf of Maine. This brook contains sea-run and year-round resident brook trout. Biologists are looking at the movement of brook trout in and out of Stanley Brook. Brook trout are caught and tagged with electronic transmitters. A data-logging receiver has been installed a short distance upstream of the estuary. This receiver is capable of determining which individuals are passing and whether they are going up into the stream or down to the ocean. Very interesting to say the least !
A similar project is getting under way in Cove Brook in Winterport. This stream drains into the lower Penobscot River approximately 11.5 miles above the Waldo-Hancock Bridge. This stream is unlike Stanley Brook in that it has different fish species,
different land uses, and drains into the Penobscot River instead of the Gulf of Maine. A University of Maine graduate student will be leading this project.
IF&W fisheries biologists began an expanded stream survey effort last year. This effort focuses on brook trout in streams that have never been surveyed. After surveying hundreds of stream sites we have a better idea of brook trout status in several areas of the state. We are a long way, however, from seeing the complete picture. Many sites were in coastal streams and allowed us to identify new sea-run trout streams and update existing data concerning trout in coastal habitats. I have sampled several of these fish and they are a sight to see. One indication that you have found a salter stream is when you spook a 12-inch trout out from its hiding place as you step across a small coastal brook.
There are sea-run trout streams and rivers scattered up and down the Maine coast. With a little leg work, you may find a small stream with a small pool and a big trout. And remember: take a youngster fishing with you and let the kid have the first cast at a truly great fish.
-- By Zachary Glidden, Fisheries Technician, Fisheries Research Section, Bangor
Submitted by : Deborah Turcotte, Acting Public Relations Representative
Maine Department of Inland Fisheries and Wildlife
SHS 41
284 State St.
Augusta, ME 04333
W: (207) 287-6008, C: (207) 592-1164