ArrayJanuary 11, 2016 at 1:07 pm
By Francis Brautigam, Regional Fisheries Biologist
[caption id="attachment_1193" align="alignleft" width="300"] September 2015 netting of Little Concord Pond reclaimed in 2011[/caption]
Our agency is sometimes criticized for “not doing enough” to combat the alarming proliferation of illegal fish introductions that threaten Maine’s unique native fisheries, but in reality restoration using the most effective method (chemical reclamation) offers promise in very few situations. This is because the process to remove invasive fish is very complex and time consuming, considering logistical, environmental, and social concerns, as well as funding availability, the use of statewide staff, and landowner support. Only when all these components align can invasive fish be eradicated through the application of an organic chemical called rotenone.
The Sebago Chapter of Trout Unlimited sought to address two potential impediments in the eradication of invasive fish and restoration of brook trout fisheries in the Sebago Lake Region; funding and “boots on the ground” volunteer support. This effort developed into a partnership that came to be known as the “5 in 5” campaign, creating an expectation that the Department would strive to restore five ponds in five years. With the treatment of Round Pond (Albany) this past fall we completed our fifth project under “5 in 5”. What began as a project starter developed into a partnership that benefited the Department, TU, and Maine’s angling community, but before I get to the “warm and fuzzy” stuff let me offer some insight regarding the challenges of our most recent reclamation on Round Pond.
Several small ponds nestled in the foothills of the White Mountain National Forest (WMNF) support native brook trout fisheries that have been managed by the Department since the 1950s. Unfortunately, other species of competing fish not native to these waters have been introduced, compromising the integrity of the brook trout fisheries and altering the ecology of these small ponds. Unlike the vast majority of other waters in the state that have suffered the same fate, sometimes referred to as biological pollution, a rather unique alignment of priorities and collaboration between state, federal, and private entities have embraced a concerted effort to restore three ponds (Round Pond, Broken Bridge, and Crocker) in the WMNF over the last two years. The success of this collaborative effort is partially rooted in a shared vision and commitment to restore and conserve native flora and fauna.
Round Pond was without question one of the most complex reclamation treatments undertaken by the Department in recent history. Restoring Round Pond necessitated the eradication of hardy brown bullhead and golden shiners from the entire watershed. A long history of beaver and beaver dam construction in the watershed necessitated temporary breaching of more than 50 beaver dams over several years (see photo 1). An expansive drainage area required treatment, including a long inlet and outlet with flowages and numerous boggy inlets. Logistics were further complicated by very limited access for equipment and personnel. The unusually hot air temperatures experienced this fall created atypical safety concerns for applicators working in rough terrain while wearing required personal protection equipment including rubber gloves, full face masks and non-breathable pants/coats.
Available fisheries staff from around the state were mobilized under a number of well-planned and creative treatment strategies that included compartmentalization of the expansive treatment area by installing six temporary sand bag coffer dams (to create temporary fish barriers). Several tons of sand bags were brought in for this purpose, and the largest dam was over 80 feet long and three feet in height. Multiple teams methodically treated all compartments within the treatment area. In addition head ponds and flowages were partially dewatered to improve drainage for access, reduce the area/volume treated, and create storage capacity to attenuate precipitation runoff that would otherwise dilute treated areas. Water level management was accomplished using pumps, passive siphoning techniques, beaver dam removals, and temporary dam creation. Foot access to all treated flowing water was improved, surveyed and marked with flagging prior to treatment. Newer application methods including the use of drip cans and “dough balls” were utilized to provide extended treatment in areas of flowing water. In addition, “difficult areas” were treated twice to not only ensure complete coverage, but also to ensure the eradication of any golden shiner fry that may have hatched since initial treatment. Golden shiners are known to spawn throughout the open water season and their eggs are more resistant to rotenone and treated flowing waters do not remain toxic for very long. The pond has a long history of Department stocking so there was no need to incur additional expense to conserve the genetic integrity of the brook trout population.
[caption id="attachment_1194" align="aligncenter" width="654"] One of over 50 beaver dams temporarily breached at Round Pond.[/caption]
The success of the Round Pond treatment will not be known for several years, but recent monitoring on the first pond (Little Concord Pond - Woodstock) reclaimed under “5 in 5” in 2011 indicated a successful treatment (no invasives captured) and the development of a high quality, multiage class brook trout fishery supporting trout up to 3 pounds (see photo 2). In addition, while the brook trout fishery was historically maintained by annual hatchery stocking, recent sampling revealed an abundance of juvenile wild brook trout. Additional assessment of wild trout production is planned to assess the need for future stocking.
As I reflect on all five reclamations (two were completed outside the WMNF) recently completed in the Sebago Lake Region, including the unique challenges and public expectations of each project, the extremely difficult and at times demanding physical work, and long work days required I can honestly say these restoration projects have been among the most challenging in my 20 year career with IFW, but also some of the most rewarding. Recent efforts have eradicated invasive fish from but a small number of infested waters in southern Maine, but have restored high quality native brook trout fisheries in a region of the state where few such fisheries exist. Additional success can also be measured in the mutually beneficial partnerships created in southern Maine; they have served to meet agency stewardship responsibilities, while furthering conservation goals in the private sector that have brought Trout Unlimited well deserved recognition and a boost in membership. To the angler it may be just good enough knowing that some good brook trout fishing was restored.
Categories