In this Section:

	Background
	Project Overview
	Project Components:
	Physical Characteristics
	Social Vulnerability
	Impacts
	Monitoring
	References
	Related Links
	Contacts

Colorado River near Lake Powell in March 2002 (top) and March 2003 (bottom).
Credit: John Dohrenwend

Research and Products:
Drought Planning and Mitigation

Economic, Social, and Ecological Impacts

Overview | Research Methods | Results

Overview

These studies examine the “unseen” social and ecological impacts of drought that go beyond the more obvious desiccated soils or restrictions on water use. CLIMAS researchers are looking at the impacts that drought has on social systems such as public recreation on federal, state, and local protected lands. CLIMAS researchers are also looking at the relationship of drought conditions to wildlife habitat and population viability, both throughout the state and specifically in the interface between urban and rural areas. The objectives of these studies are to compile information on drought impacts and to estimate economic and other quantifiable effects of drought in complex sectors such as tourism and wildlife management. Another objective is to create a comprehensive database and timeline of Arizona drought impacts.

Since effects of drought are initially subtle and gradual, negative impacts on recreational activities and local economies may be difficult to detect. Impacts may also differentially affect sectors of the economy. A drought may directly cause monetary loss by requiring more water to maintain hotel grounds, or may indirectly affect a town’s economy when a nearby state park closure limits visitors in the area.

Figure 6. Endangered Sonoran pronghorn fawn survival (shown here as fawns alive at the end of December per 100 adult females in southwestern Arizona) is linked to winter precipitation. [more details]

During drought, wildlife experience impacts that people do not, since humans can react to drought by transferring water, digging wells, and importing food. Drought directly reduces water supplies in the desert, and indirectly affects the health of wildlife populations by decreasing vegetation quantity or quality (Figure 6). Neither past wildlife ecology nor past climatology studies have attempted to describe comprehensive effects of drought on wildlife populations and behavior. CLIMAS research on animal habitat use, survivorship, and incidence of human/wildlife conflicts during drought will help the Governor’s Drought Task Force consider drought impacts on wildlife, a sector of the population usually ignored in impacts assessments.

Research Methods

CLIMAS researchers have focused on drought’s impacts on tourism and recreation, both in urban areas and protected lands. Data have been compiled for visitation to all National Park Service lands and State Parks in Arizona (daily and annually over several years before, during, and after drought), and for “bed taxes” collected by hotels. To evaluate how visitation in Arizona has changed during drought, which occurs at different scales and severities across the state, researchers organized the data by climate division. Each National Park, Monument, Recreational Area, or State Park fits within the larger boundaries of a climate division. Visitation data are then compared with climate division drought indicator data, in order to determine relationships between changes in visitation levels and recorded drought episodes.

In general, statewide wildlife population and conflict records are inconsistent and of relatively short duration. However, reliable data on game animals, endangered species, and animals that have entered urban areas are available for at least the past 10 years. From a review of hunting permit data and private hunters' records, researchers can see that hunters and hunting managers, in particular, rely on climate information to determine game animal abundance, distribution, and potential hunter success. Records kept on declining endangered populations or increasing urban encounters with wildlife may help researchers evaluate the link between drought conditions and severity with wildlife behavior. Wildlife agency records, private animal control companies, and secondary sources such as media reports together provide numerical data on wildlife encounters (also referred to as conflicts) with people in urban areas. Statistical tests on the observational data can assess whether conflicts increased during drought or immediately following. Literature on desert wildlife documents a range of physiological responses to arid conditions and drought events, so inferences based on habitat decline or change due to drought may help reveal drought impacts on less-monitored wildlife.

Results

Figure 7.Trends in visitors to Slide Rock State Park. [more details]

So far, National Park visitation does not appear to be related to climate-division drought severity. Interviews with National and State Park employees point out confounding factors that may explain the lack of a significant relationship between drought and visitation. Since many National Parks have international prominence as tourist attractions, people plan vacations without considering changest to the ecological health or aesthetics of a park during drought. Broader issues may also affect visitation, such as domestic terrorism threats, which also determine whether people choose to travel internationally or far from home to visit Arizona's natural attractions.

Visitation data from State—rather than National—Parks may better reflect changes in recreation, or in peoples’ willingness or ability to camp, hunt, fish, or canoe in protected lands (Figure 7). Because people often visit parks near their homes, the forecasts and media reports concerning drought also reflect conditions—and consciousness of these conditions—in their immediate vicinity. Other information on municipal, industrial, and agricultural sectors in Arizona will augment the economic impacts analysis.

A timeline of drought status, habitat conditions, and related impacts on wildlife populations, as well as a statistical analysis of the relation of climate conditions to urban wildlife/human encounters, will inform the Drought Task Force monitoring committee as they refine the process of selecting robust indicators for triggering drought mitigation and response actions.

The objectives of future research include the evaluation of economic impacts of drought in the parts of the agriculture and tourism sectors. In addition, researchers will analyze the factors that confound simple linear relationships between drought and wildlife impacts, including urban sprawl, highway and border construction, ranching, artificial waters, and both human and animal behaviors.