After several months of intensive work, CDFW teams have developed draft conservation strategies for 39 Conservation Units (USDA Ecoregions, USGS HUC 4 Watersheds, and MLPA Marine Study Regions). A state map of the Conservations Units can be found here. A summary of the Conservation Strategies, Key Ecological Attributes, Stresses, and Threats for each conservation unit can be found here.
Each Conservation Unit represents and encompasses the full suite of biodiversity and ecosystem functions & conditions found within or nearby their geographical area. Examples of Conservation Units include: Southern California Coast Ecoregion 261B, Southern California Coast Hydrologic Unit (HUC) 1807, and the South Coast Marine Conservation Unit.
Within each Conservation Unit, one or more Targets were selected to develop conservation strategies for. Targets for conservation units consist of vegetative communities or habitats, native fish assemblages, and marine habitats. Examples of targets include: California Annual and Perennial Grassland, South Coast Native fish Assemblage, and Bays, Estuaries and Lagoons.
The purpose of the conservation strategies is to identify actions that will improve the conditions of the ecosystems under focus. Those identified actions when properly implemented are intended to accumulatively benefit the Species of Greatest Conservation Need found in those conservation units and beyond.
To begin the analysis, Key Ecological Attributes (KEAs) were identified for each target. KEAs are the most critical ecological components of a target, often related to the life history, habitat, ecosystem processes, or community interactions that the target depends upon, without which its persistence would be impaired. Often, if those KEAs are degraded or missing in a conservation unit where the target is found, it could impact the integrity and viability of the ecosystem by interrupting the dynamic interaction among vegetation, water, soil, atmosphere, biota, and so on. Examples of KEAs are area and extent of community, biotic interactions and hydrologic regimes.
Teams then identified the environmental stresses affecting each conservation target. Stresses are related to “naturally” occurring phenomena such as drought, fire, blizzard, etc., and are best described as the degraded condition of the KEAs. The teams next identified “threats” that influence a habitat. Threats are primarily human related activities that potentially affect the conservation target. Some common examples include invasive species, dams and incompatible dam managements, incompatible transportation corridor designs, and urban development.
Understanding how KEAs, stresses, and threats interact among themselves to impact a target is the basis for developing conservation actions to improve the condition of the target. A current example facing California now is with native fish. Native fish are dependent on specific water conditions unique to the place where they evolved. Native fish can be impacted by reduced water flow (water flow = KEA, reduced water flow = stress) due to snowpack decline (stress) resulting from climate change (stress in this case), and further impacted by dam operations that release less water and alter the quantity and timing of the flow (underlines are KEAs, incompatible dam operation is the threat). Together this interaction leads to loss or degradation of habitat (stress) with less than ideal conditions, such as higher water temperatures (stress), or impaired movement within a stream (stress). Conservation strategies could be developed by considering feasible actions that reduce the impacts such as altering the timing of flow releases mimicking the seasonal flow, or retrofitting dams to allow more cold water releases.