Blue-winged Warbler Photo by Jim Rathert, Missouri Dept. of Conservation.

The Forest Bird Habitat Suitability Index Modeling Project was undertaken to give land managers a decision-support tool for bird conservation at a landscape scale.

In 2004, the North American Landbird Conservation Plan established population goals for 448 species of terrestrial birds across the continent. Where increases in numbers are desired, goals are phrased in proportions, such as increasing a population 50% or 100%, with those targets typically being the proportion needed to return populations to the levels at the beginning of the North American Breeding Bird Survey in the late 1960s. Joint Ventures have been given the task of coordinating efforts within and among Bird Conservation Regions to reach regional goals.

To translate the targets set by the Conservation Plan into local management decisions, land managers need to know how habitat relates to numbers of birds. The Forest Bird Habitat Suitability Index Modeling Project provides a link between habitat and population size for priority species of forest birds found in the Central Hardwoods and the West Gulf Coastal Plain/Ouachita Mountains Bird Conservation Regions.

Land managers can use the models to answer questions about the quality and distribution of habitat for given species within the two Bird Conservation Regions, changes in habitat suitability and population size over time, and the predicted effects of management decisions on priority, forest-breeding bird populations.

Models were created for the Central Hardwoods and the West Gulf Coastal Plain/Ouachita Mountains BCRs. The methods can be used to create models for other areas.

The models were created at the Bailey's Subsection level.

Habitat Suitability Index models were generated for each of 40 species of forest-breeding birds, using data from the literature and species experts. Habitat variables were then correlated with the landscape, using the National Land Cover Dataset, the National Elevation Dataset, and the National Hydrography Dataset. Forest structure variables, at subsection resolution, were derived from the US Forest Service's Forest Inventory Analysis data. To assess changes over time, models were generated separately using 1992 and 2001 Land Cover and concurrent Forest Inventory Analysis data.

The models were unveiled to Central Hardwoods Joint Venture and Lower Mississippi Valley Joint Venture partners at a three-day training session held in Memphis in April. Over forty representatives from universities, state and federal agencies, non-profit organizations and joint ventures learned how they can use the models to understand current habitat conditions, identify limiting conditions at the subsection scale, estimate current population sizes, monitor changes in habitat suitability, and predict the effects of management decisions on habitat suitability and consequent population sizes. Attendees included representatives from the following organizations:

To introduce the bird conservation community at large to the methods and capabilities of this modeling approach, a workshop was held at the 2008 Partners in Flight conference in McAllen, Texas.

The significance of this work was recognized with a Wings Across the Americas Award from the US Forest Service in 2008.

Link to Forest Bird HSI Modeling Site

The Forest Bird HSI Modeling Project generated models such as this one, which maps the Habitat Suitability Index for Blue-winged Warblers across the Central Hardwoods and West Gulf Coastal Plain/Ouachita Mountains Bird Conservation Regions.HSI values vary from 0 (least suitable) to 1 (most suitable). Landcover and Forest Inventory Analysis data from 2001 were used to generate the model.

• Lower Mississippi Valley Joint Venture
• University of Missouri
• US Fish and Wildlife Service
• US Forest Service Forest Inventory and Analysis Program
• US Forest Service North Central Experiment Station
• US Geological Survey