This dataset is a component of a complete package of products from the Connect the Connecticut project. Connect the Connecticut is a collaborative effort to identify shared priorities for conserving the Connecticut River Watershed for future generations, considering the value of fish and wildlife species and the natural ecosystems they inhabit. Click here to download the full data package, including all documentation.
These datasets represent aquatic core areas and aquatic buffers, in combination with terrestrial cores and connectors they spatially represent the ecological network derived from the CTR LCD project.
Lotic cores: This set of lotic (river and stream) core areas, in combination with the lotic cores and terrestrial cores and connectors, they spatially represent the ecological network derived from the CTR LCD project. The network is designed to provide strategic guidance for conserving natural areas, and the fish, wildlife, and other components of biodiversity that they support, within the Connecticut River watershed. Core areas serve as the foundation of the conservation design. They reflect decisions by the CTR LCD planning team about the highest priority areas for sustaining the long-term ecological values of the watershed, based on currently available, regional-scale information. Lotic cores represent the following:
- streams of relatively high ecological integrity across all lotic (i.e., riverine) ecosystem types, emphasizing rivers and streams that are relatively intact (i.e., free from human modifications and disturbance locally and within the upstream catchments) and resilient to environmental changes (e.g., climate change). Integrity has the potential to remain high, both in the short-term due to the connectivity to similar natural environments within the riverine network, and in the long-term for headwater streams due to the relative insensitivity of stream temperature to air temperature changes;
- headwater streams of relatively high current habitat value (i.e., landscape capability) for brook trout, emphasizing streams that provide the best habitat conditions under current climate conditions; and
- Large and medium rivers that provide habitat for anadromous fish, including the portions of the mainstem and major tributaries of the Connecticut River from the mouth of the river upstream to the limit of passability for American shad, blueback herring, shortnose sturgeon, alewife, and sea lamprey.
Core areas are built from focal areas with high value based on one or more of the attributes listed above. These “seed areas” are expanded upstream and downstream to include areas that provide additional ecological value and resilience to long-term change and to encompass a minimum of 1 km in stream length. Consequently, the cores may include sections of lower-valued streams and extend beyond road-stream crossings; however, they do not extend past dams.shp. Collectively, lotic core areas encompass 28% of the total stream length in the CTR watershed, as decided by the partnership. A total of 523 lotic core areas have been identified, ranging in stream length from 1 to 442 km, with an average stream length of 16 km.
Lentic cores: This set of lentic core areas, in combination with the lotic cores and terrestrial cores and connectors, they spatially represent the ecological network derived from the CTR LCD project. The network is designed to provide strategic guidance for conservation of natural areas, and the fish, wildlife, and other components of biodiversity that they support, within the Connecticut River watershed.
Core areas serve as the foundation of the conservation design. They reflect decisions by the CT River LCD planning team about the highest priority areas for sustaining the long-term ecological values of the watershed, based on currently available, regional-scale information. Lentic cores represent the following:
1) lakes and ponds of relatively high ecological integrity, emphasizing lakes and ponds that are relatively intact (i.e., free from human modifications and disturbance locally and within the water body catchment) and resilient to environmental changes (e.g., climate change) due to their size and connectivity to similar natural environments.
Lentic core areas are built from focal areas in ponds and lakes with high ecological integrity. These “seed areas” are expanded to include the entire water body in order to create logical conservation units. Consequently, the larger lentic cores may include partially-developed shorelines. Collectively, lentic core areas encompass 27% of the total area of ponds and lakes in the CTR watershed, as decided by the partnership. Note, Quabbin Reservoir, which itself comprises 20% of the total area of ponds and lakes in the CTR watershed, was not included as a lentic core in this scenario. A total of 1,206 lentic core areas have been identified, ranging in size from 0.06 to 1,323 ha, with an average size of 11.7 ha.
Aquatic buffers: This dataset buffers around the aquatic (lotic and lentic) cores. Aquatic buffers spatially represent the areas estimated to have a strong influence on the integrity of the aquatic cores based on watershed processes. Specifically, the buffers represent areas hydrologically connected to the aquatic cores through surface runoff and instream flow processes, such that anthropogenic stressors within the buffers are likely to adversely impact the integrity of the aquatic cores. Importantly, the buffers represent places upstream and upslope of the cores where human activities such as development, and point and non-point pollution, etc., may have a strong impact on the ecological condition of the cores. Unlike the cores, therefore, the buffers do not necessarily represent areas of high ecological integrity.
Buffers are established for all aquatic cores (both lotic and lentic) based on a time-of-flow model that extends as a gradient upstream and upslope from the cores, varying in distance depending on slope and land cover. Areas immediately upstream and upslope of the cores have the greatest influence (i.e., shortest time-of-flow). The influence decreases much faster across land than water so that the buffer typically extends much farther upstream than upslope from the core. Thus, the buffer does not represent a discrete zone distinguishing “inside” from “outside” of the buffer. Rather, it represents a graduated zone of influence in which cells upstream and closer to the core have greater influence. Cells in the upland and farther from the stream, especially on flat slopes with forest cover, have less influence. In addition, the graduated zone of influence increases in size with decreasing stream size. The zone of influence on larger rivers tends to be relatively narrow, whereas the zone of influence on headwater creeks tends to be wider and often encompasses the entire upstream catchment.
