Full report - Conservation Gateway

Chapter 1 - IntroductionSpecies and Habitats SelectionA suite of habitats and species, characteristic and representativeof the full diversity of the region were selectedin consultation with external technical advisors. TheConservancy’s standard conservation planning methodsusually refers to the habitats and species one seeks to conserveas conservation targets. Although this methodologyhas been adopted or modified by many groups around theworld, the terminology can be confusing. In this report,conservation targets are simply the habitats, species, andprocesses we focused on and not targets in the sense ofnumerical goals.The concept of coarse and fine filters was used in selectingconservation targets in this assessment. The “coarse filter”approach is based on the efficiency of using large-scalehabitat conservation strategies to benefit many species atonce. Two habitat targets, coastal shorelines and benthichabitats, were indentified to serve as coarse filters to accountfor all the species and processes that they support.Both of these habitats were mapped comprehensivelyacross the region, classified into many subtypes based onstructure and composition, and characterized in detail.This analysis was designed to facilitate selection of a suiteof priority conservation areas representing some of thebest examples of each habitat type for the second phase ofthis assessment.However, habitat conservation alone is not sufficient forconserving all species and so with guidance from eachtechnical team, a “fine filter” approach was used to select asubset of the thousands of species found within the studyarea. Because it is not practical or feasible to produce a detailedand spatially explicit analysis for every species in theregion, the teams identified focal species in considerationof representation, ecological guilds and processes, and rarity.For each species team, a set of 8 to 50 individual specieswere identified and a set of individual analyses weredone for each species.priority conservation areas. In a few instances, such asseabirds, species concentration areas were identified astargets in their own right. All of the conservation targetsare listed below and described in detail in the chapters ofthis report.Coastal EcosystemsThe fringing ribbons of habitats that make up the landseainterface help maintain marine diversity and playcritical roles for both nearshore and offshore plants andanimals. The Northwest Atlantic coastline is particularlywell known for several large and hundreds of smallproductive estuaries that provide juvenile nursery andspawning grounds for fish, mollusks, seabirds, and crabs.Recognizing the heterogeneity and ever-changing natureof the coastline, this section of the assessment reviews thehistory of coastal systems in the region, provides an overviewof coastal habitats such as salt marshes, seagrass beds,and oyster reefs, examines some of the threats and humaninteractions with these systems, provides an in-depth lookat sea level rise and reviews potential strategies for enhancingresilience of coastal systems. This report focusesspecifically on the contributions that coastal ecosystemsmake to marine diversity.Benthic HabitatsIn Northwest Atlantic region, benthic (or seafloor) habitatscontain over 2000 species of invertebrates such asmarine worms, sponges, shrimp, crab, clams, scallops,snails, sea stars, corals, anemone. , and. Because individualspecies are adapted to variations in the environment suchas sediment grain size, topography and depth, a benthichabitat type is defined as a group of organisms repeatedlyfound together within a specific environmental setting.For example, silt flats in shallow water are characterizedby specific amphipods, clams, whelks and snails. In thisassessment, we identified and mapped over 90 of the mostcommon habitats with characteristic benthic communitiesdistributed throughout each subregion.Phase Two of this assessment integrates the individualspatial data for all conservation targets to identify high1-Northwest Atlantic Marine Ecoregional Assessment • Phase 1 Report