River birds, raptors, and river herring – read all about the Maine River Bird Project!

October 15, 2015 at 11:27 am

By Erynn Call, MDIFW State Raptor Specialist [caption id="attachment_1012" align="aligncenter" width="713"]Osprey such as this one frequent waterways with large river herring runs. (Photo courtesy of Sharon Fiedler) Osprey such as this one frequent waterways with large river herring runs. (Photo courtesy of Sharon Fiedler)[/caption]   The Maine River Bird Project is dedicated to expanding awareness and improving species and habitat conservation within Maine’s rivers.  Our mission is to better understand rivers, river birds, and ecosystem change through citizen science, collaborative research, and educational outreach.  River birds include waterfowl, wading and shorebirds, some passerines, raptors such as Osprey and Bald Eagle, and rare, threatened, endangered, and species of special concern within each group. Linkages between river birds and river features such as water flow, presence of dams, and landscape composition not only inform our current understanding but also serve as a baseline to monitor ecosystem change associated with river restoration and return of sea-run fishes (Maine hosts 12 fish species that require movement between ocean and rivers to live and reproduce). [caption id="attachment_1014" align="alignleft" width="388"]a collaboration The Sebasticook River hosts the largest river herring spawning run in the northeast, and is a critical resource for a number of species including bald eagles.[/caption] Initiated in 2008, the project includes completed, ongoing, and newly initiated objectives.  Thus far, we documented how dams alter the transfer of nutrients from sea-run fishes to river birds, and how bird abundance relates to river features.  Analysis of feather and prey samples collected along the Penobscot River suggested that prior to its removal, the lowermost dam on the Penobscot (Veazie) acted as a barrier to the delivery of nutrients from sea-run fishes to Bald Eagle and Belted Kingfisher nestlings upriver.  We expect that these nutrients will be detected in future sampling of nestlings upriver as sea-run fish populations move upstream following the removal of the Veazie and Great Works dams. Additionally, year-round river bird survey observations collected by experienced citizen scientist birders across 10 Maine rivers were combined with river feature data.  The results of this analysis informed our current understanding of species-habitat relations and with ongoing monitoring, will shed light on ecosystem changes associated with urbanization and river restoration. In 2014, the Maine Department of Inland Fisheries and Wildlife (MDIFW) collaborated with the University of Maine - Orono, Unity College, and Biodiversity Research Institute (BRI) to establish additional survey sites along the Sebasticook River.  The 5-mile stretch between the Benton Falls dam and the confluence with the Kennebec River in Winslow hosts the largest river herring spawning run in the Northeast. Over 3 million river herring, a collective term for alewife and blueback herring, attract Bald Eagle and Osprey from mid-May to early July.  We are learning about the extent and timing of use of these river stretches, and difference between these two river bird species.  Results from 2015 are pending; however, on June 13, 2014, 64 eagles were observed across all sites; the largest aggregation ever documented in New England.  MDIFW worked with BRI to develop an educational flyer highlighting the importance of this run to Bald Eagles.    MDIFW will continue to lead monitoring along the Sebasticook River, in collaboration with the Sebasticook Regional Land Trust and landowners, and pursue additional river herring runs across the state (see surveyor needs below). In terms of outreach, the MRBP coordinator shares progress and results through quarterly newsletters with river bird citizen scientists and partners.  Awareness of the projects accomplishments are also bolstered through presentations at various national and local meetings. [caption id="attachment_1011" align="alignright" width="434"]Volunteers are needed to help document the use of river herring by bald eagles and osprey. Volunteers are needed to help document the presence of river birds. (photo courtesy of Lea Ramirez)[/caption] If you are an experienced birder and would like to get involved contact Erynn Call at erynn.call@maine.gov and check out the opportunities below:
  • River bird surveyor needs:
    • We are looking for birders interested in surveying the Oosoola Park Boat Landing in Norridgewock along the Kennebec River.
    • Considering the potential removal of the dam in Westbrook (Saccarappa Dam), we are looking for a surveyor for our historical (not surveyed in recent years) river bird survey sites above and below the dam.
  • River herring – river raptor surveyor needs: Please contact us if you are interested in getting involved in the river herring – river raptor surveys.  These surveys are slightly different than the standard river bird survey with the purpose of examining Bald Eagle and Osprey use of river herring. Surveys are conducted from May to early July during the river herring spawning run at a string of adjacent sites along the river bank.   Let us know if you have river herring runs that you would be interested in monitoring in addition to these two sites listed below:
    • Sebasticook River:  5 survey sites downriver of the Benton Falls Dam, surveys at the 5 sites can be completed in about 3 hours, surveys conducted 1 – 2 days per week.   Data collection for these sites began in 2014.
    • Outlet Stream between Sebasticook River and China Lake:  Establishment of sites is pending in 2016 surveyor involvement.