Indicators: Physical Habitat Complexity

What is physical habitat complexity?

Physical habitat complexity measures the amount and variety of all types of cover, both living and non-living, at the water’s edge in lakes. These features include vegetative cover such as overhanging or submerged tree limbs, shrubs and other plants growing along the shore, and non-living features such as boulders, rock ledges and undercut banks that provide habitat and refuge for organisms at the land-water interface.

Why is it important to evaluate physical habitat complexity?

Since it combines data on both shoreline and shallow water components of habitat, this indicator provides a comprehensive view of the diversity and complexity of habitat found near the water’s edge, and its ability to buffer lakes against human disturbances such as polluted runoff. 

What can physical habitat complexity tell us about the condition of water?

Lake shore conditions vary naturally between different ecological regions of the U.S. In general, lakes with dense and diverse shoreline vegetative cover and also with complex physical features at the land-water interface are generally better able to support aquatic organisms. 

How is this indicator used in NARS? 

Two surveys collect data on physical habitat complexity. Data are available on the NARS data page for these surveys. Below the table you access assessment information in current reports.

NLA	NRSA	NCCA	NWCA	Indicator Type
X	X			Core Indicator
				Research Indicator

National Lakes Assessment Web Report – Physical Habitat Complexity Results 

National Rivers and Streams Assessment Web Report – Physical Habitat Complexity Results