Operational Plan for the Restoration of Diadromous Fishes to the ...

Appendix G - Habitat Survey and Assessment Plan for the Penobscot Basin
Author: Greg Mackey
Currently there is substantial coverage of Atlantic salmon habitat survey in the
Penobscot basin. However, the size of the basin precludes any type of
comprehensive field survey of salmon habitat. Such surveys are valuable because
they not only provide data of immediate use to managers and policy makes, but also
provide baseline data for various modeling efforts. In addition to the field survey of
habitat, the entire Penobscot basin, as well as all Atlantic salmon waters in the state,
has had Atlantic salmon habitat estimated via a GIS model. Further refinement of
this model is planned.
Habitat Survey
Field survey of habitat should continue to use the DMR BSRFH “Big River” habitat
survey method and focus on waters of importance to salmon management, but also
focus on surveying a diversity of stream types (size, gradient, geographic location).
This will help managers understand the scope and frequency of habitat across
various stream types. Such surveys will also help to validate modeling efforts,
providing more and faster habitat information with estimates of precision at lower
cost. A sampling plan for habitat survey will be established by biologists familiar with
the basin and with the GIS habitat model. Such a survey may include stream
reaches randomly chosen for a defined sampling frame. On an annual basis, a
portion of each summer will be allotted to habitat survey, with balance between
habitat assessment and survey.
Habitat Assessment
Large Woody Debris
Recent surveys in coastal Maine rivers have revealed that large woody debris (LWD)
is at extremely low levels. A study is underway to test the effectiveness of adding
LWD to salmon habitat. However, no surveys have been done in the Penobscot
basin, nor in more inland Maine rivers. The Penobscot basin contains a wider array
of land use activities, forest types, and landscape features than does the coastal
area where previous surveys were done. Therefore, performing LWD surveys
across reaches with different stream sizes, forest stands, topography, and land use
history would help link LWD loading to these variables. Assuming a link is revealed,
we can use this information to predict LWSD loadings in other streams. One avenue
that may aid in this is using an LWD loading model based on forest stand data,
environmental variables, and stochastic events. Field surveys will help validate the
model and allow broader inferences to be made.
PRFP Page 187