The Otter's Tale Newsletter

The following articles are selections from our quarterly newsletter: "The Otter's Tale". The entire newsletter is available at the Estuary Center and is mailed to current members of the OPCA.

It "Otter" Be Beaver Point Creek

by Kriste Garman, Park Manager

Journal entry, Saturday, March 27, 2010, 4:30 p.m., Wood Duck Canoe Trip—Headed across “the big open” on Otter Point Creek due to extremely high water making it impossible to get the canoe rig across OPC at Bosely. The customary marsh landmarks are all submerged, challenging the mental map.

As we head up the stream channel past wood duck box #1, we have the first sighting of a semi-aquatic mammal—seems small, but can’t see the tail to make a positive ID—muskrat or beaver? We pass a low-profile, widened conical “lodge” topped with leafy vegetation that looks more like muskrat than beaver.

Glancing to the left as we pass Snake Island, we notice a field of what looks like “punji sticks” marching across the island. What seems like hundreds of saplings, from 1.5 to 4 inches in diameter, have been cut off at a uniform height of about 18-24 inches, each cut end having a conical shape, like a sharpened pencil. With no understory leafed out, looking up from water level, the stumps look like a bed of nails.

This is the first big indicator of increased beaver activity we see.

Turning up the right-hand channel past Snake Island, we see a beaver crossing the creek in front of us. It seems to have a “which way do I go, which way do I go?” panic moment as it turns back the way it came, then reverses again to the opposite shore, and then dives with a warning slap of its tail on the water. It seems to be heading toward a new (since last fall) lodge right on the edge of the channel, covered with many branches (perhaps taken from Snake Island?). These guys have been busy. Early spring is when most colonization activity takes place, as the two and three year old beavers leave their natal colonies to establish their own. If food supply is depleted, beavers will also colonize new areas.

Just upstream, on the bank opposite the new lodge, we see two 12 inch by 8 inch mud towers, side by side, looking like a new condo construction site for small mammals. These are scent mounds, built and marked with urine and smelly castoreum (from the castor gland of Castor canadensis). Both male and female beavers will mark territory this way, protecting their colonies’ food supply from other beaver colonies or individuals. Research from Alaska has shown that beaver colonies need a minimum habitat area of .8 kilometers of stream length versus 1.3 square kilometers of marsh. Wonder what minimums are here.

As we continue upstream taking the right fork past lagoon #1, we see another beaver swimming across the creek. On the left bank there are several large (12" or larger) standing trees that have been chewed, bark removed all around the trunk about 18 to 24 inches above ground level. A little further along we see a fallen tree that has recently had the trunk bark completely chewed off, tip to base. Beavers have specially adapted digestive systems that allow them to digest about 33% of the cellulose they consume in all that woody vegetation. They particularly enjoy willow and birch in this area, but seem to also harvest maple and oak, and supplement with herbaceous vegetation such as cattails and sedges in the warmer months.

A dark shadow moves just past that log, and as we pass in front of it, we apparently have timed our appearance just right to catch the beaver on the shore, with no time to slip unnoticed into the water. It freezes, in its curious down-in-front, haunches up position, and remains still and watchful and …grouchy looking, until all eight canoes have slipped by. It’s a first for me—the beavers usually seem to know we’re there long before we know they’re there, and move away. They have an excellent sense of smell and hearing that aids their early warning system. This guy gave us the opportunity to note his large body size, rich brown fur coat, and small and beady brown eyes that did indeed look disgruntled at being caught!

We have seen and heard several wood ducks this evening, but the beavers are definitely stealing the show. And the otters are nowhere to be seen….

The number of beaver we see, as well as the amount of damage to trees, raises many questions. Is the beaver population expanding? Are they displacing other desirable species? Often wondered is whether expanding beaver populations affect otter populations in any way. What species of vegetation are the beaver eating, and are they depleting those species? Is their feeding and dam building behavior affecting hydrology in the marsh? What will happen to Snake Island if beaver activity continues unabated and all large woody vegetation dies?

Increased incidence of girdling and subsequent death of many of the large trees at the Bosely Conservancy has caused much concern about the beaver population within the Izaak Walton League, a conservation group which owns the Bosely Conservancy. In the 2008-09 winter season, they authorized beaver trapping within the Conservancy and harvested 13 animals. Still we see what seems to be a downstream expansion of beaver territories.

During the summer of 2009 intern Bernard Schuler, who is studying Wildlife Management at Virginia Tech, launched a study of beaver activity in the area of the Bosely Conservancy. The objectives of the study were to assess beaver damage in the area and help the park managers create an action plan to deal with the tree damage. Field work consisted of surveying the vegetation around the lagoons to determine the species and sizes of trees affected by beaver activity. Bernard determined that river birch and black cherry saplings were the species most often removed for eating and lodge-building by the beavers. Large old trees in the vicinity of the water were often damaged or killed from being gnawed and girdled. It is the loss of these large trees that most concerns park managers. Bernard suggested protecting the trees from damage by applying wire mesh around the base.

The OPCA hopes to continue this research during the summer of 2010 to answer more questions about the beaver on Otter Point Creek. If you are interested in the summer internship position, please contact the Estuary Center, or check our website.

The Estuary Center Needs YOU!

by Tina Peek, Marketing and Promotions Coordinator

The Otter Point Creek Alliance is looking for new committee members for its Board. What exactly is the Otter Point Creek Alliance? Even if you are a member you may not have much of an idea of what this nonprofit group does. The Otter Point Creek Alliance, or OPCA, is a “friends of” group dedicated to the mission of increasing awareness, understanding, and appreciation of estuarine ecosystems through research, monitoring, and education for the Anita C. Leight Estuary Center. Ways in which the Otter Point Creek Alliance supports the Estuary Center are by promoting environmental education of school children and the general public, offering volunteer opportunities, supporting research projects, sponsoring college internships, and promoting stewardship and conservation in the Reserve and surrounding area.

You may have heard the staff at the Center throwing around acronyms like NOAA and CBNERR. What do they all mean? The OPCA partners with several groups on the local, state, and federal levels to help further its mission: Harford County Parks and Recreation, the National Oceanic and Atmospheric Administration (NOAA), Chesapeake Bay National Estuarine Research Reserve (CBNERR), the Maryland Department of Natural Resources (DNR), and the Izaak Walton League. The OPCA receives funding through grants from CBNERR and DNR, and Harford County Parks and Recreation provides regular yearly funding.

But by far our most important source of funding is from members like YOU! Programs, events, and other activities wouldn’t be possible without your membership dues, donations, and fees for programs. Please consider an additional donation above and beyond your regular membership dues. Check out the new benefits for different donation levels on our website www.otterpointcreek.org. Volunteers also play a vital role in the day to day workings of the Estuary Center. Research, monitoring, trail maintenance, programs, and special events are just a few of the areas where volunteers are needed.

Another area where volunteers are needed is on the OPCA Board. These dedicated volunteers meet every other month to decide on important events and activities, manage funds, and make administrative decisions for the OPCA. The Board is comprised of two co-presidents - Rob Roemer and Sharyn Spray, a vice president – Bill Murphy, and a secretary – Virginia Cobler. The OPCA currently has two part-time paid positions, the treasurer and a marketing and promotions coordinator. Other members of the Board include Eugene Burg, Michele Dobson, Andrea Musser, Barry Napp, Ellen O’Hanlon, Charlotte O’Reilly, Phil Powers, and Donna Yorkston. The Board is currently looking for new committee members! The committees include Executive, Strategic Planning, Finance, Volunteer, Marketing and Promotions, Gift Shop, and Elections. If you’d like to be on a committee for the OPCA, give us a call at 410-612-1688.

More Information

Calendar of EventsView all

Volunteer Opportunity: Invasinators08/01/2010 @ 11:00 am-1:00 pmBecome a part of the volunteer team of invasive plant removers and native plant restorers. Learn why non-native invasive plants are a threat to our ecosystem, how to identify problem plants, and removal and restoration strategies. Wear sturdy shoes, long sleeves, and work gloves for field work in the Reserve each meeting date.
Canoe Trip: Up the Creek With a Paddle08/01/2010 @ 2:30 pm-5:00 pmAdventure up Otter Point Creek to seek the abundance of summer life in the estuary! We’ll go after grasses, sedges, and rushes and look for residents hiding among them. See how the estuary in summertime is the cool place to be…
Canoe Explorations Summer Nature Camp08/02/2010 @ 9:00 am-4:00 pmJourney on our waters as we discover the Chesapeake Bay and its watershed by canoe. Each day we will paddle a different location in the local area. Basic instruction will be provided the first day. Bring a lunch and water bottle each day (no glass).
Nature Tots & Kids08/02/2010 @ 9:00 am-10:00 amExplore and discover the natural world around us during the summer season through sensory activities, songs, movement and a short hike.
Nature's Playgroup: Session I08/04/2010 @ 9:00 am-10:00 amLittle ones and their parents play and learn in the natural world. Stories, songs, simple crafts and discovery outings will highlight each day's theme.