Need more help? Ask your Personal Librarian for assistance. Every major has its very own research expert ready to assist you. If you need help finding your librarian, email libraries.reference@ttu.edu.

If you need to uncover more, these resources may help.

From the Field

Water Quality: A Hidden Dangerin Anthropogenic Desert Catchments

KERRY L. GRIFFIS-KYLE,1 Department of Natural Resources Management, Texas Tech University, Lubbock, TX 79409, USA

JEFFERY J. KOVATCH, Department of Biological Sciences, Marshall University, Huntington, WV 25703, USA

CRISTINA BRADATAN, Department of Sociology, Anthropology, and Social Work, Texas Tech University, Lubbock, TX, USA

ABSTRACT Natural rock pools, tinajas, and constructed catchments in the Sonoran Desert provide waterfor a wide variety of organisms. In 2012, we monitored water quality and amphibian and dragonfly use ofwildlife waters in southwestern Arizona, USA. We measured ammonia concentrations that exceededthe U.S. Environmental Protection Agency’s guidelines for aquatic life and were well above concentrationsthat cause mortality in amphibians and other aquatic organisms. Both amphibians and dragonflies had lowerspecies richness in catchments than in the tinajas, and amphibian species richness was negatively associatedwith ammonia concentration. These concentrations of ammonia alone cause concern for the manage-ment of biodiversity, specifically for wetland-dependent organisms. Furthermore, ammonia concentrationsmay be high enough to impact terrestrial organisms of economic and conservation importance includinghumans. � 2013 The Wildlife Society.

KEY WORDS ammonia, amphibians, dragonflies, immigration, rock pool, tinaja, United States–Mexico border,wildlife waters.

Anthropogenic wildlife waters, including artificial catch-ments, are created worldwide in arid systems to supplementnaturally available water for wildlife and livestock (Har-rington et al. 1999, James et al. 1999). Supplemental water isbecoming more important as a management tool as thefrequency and duration of droughts are increasing fromglobal climate change. Artificial catchments are small surfacepools directly fed by rainwater or by sub-surface reservoirsthat collect rainwater or are manually filled. Wildlife andlivestock, including species adapted to survive on water fromfood and metabolic sources, use these sites (Rosenstocket al. 2004). In fact, rock pools in arid regions can supportbio-diverse communities of both aquatic and terrestrialorganisms (Jocque et al. 2006).In the Sonoran Desert, where wildlife historically

depended on water at natural rock pools (tinajas) and othersources, catchments provide supplemental water for targetspecies such as desert bighorn (Ovis canadensis nelsoni) andSonoran pronghorn (Antilocapra americana sonoriensis;Fig. 1). Previous studies found no evidence of avoidanceand little evidence of predation at these waters. Even so,controversy surrounds the importance and impact of thesecatchments in supporting wildlife populations (Broyles 1995,Rosenstock et al. 2001, Simpson et al. 2011).In 2012, we sampled 10 tinajas and 17 constructed

catchments across 7mountain ranges in southwesternArizona,

USA, and found significantly fewer species of tadpoles anddragonflies and often found no species present in catchmentsas compared with tinajas (Fig. 2). We found three amphibianspecies in this habitat, red-spotted toad (Anaxyrus punctatus),Sonoran toad (Incilius alvarius), and Couch’s spadefoot(Scaphiopus couchii). We sampled both types of waters from5 days to 10 days post-rainfall-event duringmornings to detecttadpoles, with some sites visited up to 3 times during theseason. Most catchments had no tadpoles, while most tinajashad �1 species of amphibian present (amphibian presencelogistic regression: x2¼ 9.2; df¼ 1, P¼ 0.002). We identifiedthe following dragonfly species at the water sites: flameskimmer (Libellula saturata), spot-winged glider (Pantalahymenaea), wandering glider (P. flavescens), roseate skimmer(Orthemis ferruginea), and common green darner (Anax junius).All the catchments had either 0 or 1 species of adult or larvaldragonflies, while the natural tinajas had 2 or 3 species each(dragonfly presence logistic regression: x2¼ 6.2; df¼ 1,P¼ 0.01; sites visited only once were excluded from theanalysis; 11 catchments, 6 tinajas).Tadpole species diversity at catchments was negatively

correlated with ammonia concentration: 27% of catchmentswere above the detection range of the test (0–50mg/LN–NH3) and 75% exceeded the Environmental ProtectionAgency’s criteria for maximum concentration for a pH of 8.2(average pH of catchments; HachDR/890 Portable Color-imeter, AmVerTM High Range Ammonia; Hach Company,Loveland, CO). These high levels of ammonia were found incatchments across the study area. These concentrations arewell above levels known to cause mortality in amphibians andinvertebrates (Camargo and Alonso 2006). The maximumconcentration in tinajas was 1mg/L N–NH3. Despite these

Received: 15 May 2013; Accepted: 19 August 2013Published: 29 October 2013

1E-mail: kerry.griffis-kyle@ttu.edu

Wildlife Society Bulletin 38(1):148–151; 2014; DOI: 10.1002/wsb.358

148 Wildlife Society Bulletin � 38(1)

concentrations at catchments, photographs showed manyspecies, including humans and lactating bighorn sheep,drinking water at catchments with high ammonia (A.Alvidrez, Department of Defense, U.S. Air Force, 56thRange Management Office, Luke Air Force Base, unpub-lished data).Ammonia accumulates from the decomposition of organic

matter and excrement from organisms. Whereas flash floodscan remove accumulated debris from tinajas, there is nonatural mechanism to remove organic material from catch-ments. In addition, accumulation of ammonia could becaused by constraints on nitrification. Nitrification may belimited when toxic conditions impact the bacteria responsiblefor nitrification (Nitrosomonas and Nitrobacter; Anthonisen

et al. 1976), or when there is an insufficient amount ofoxygen for the chemical reaction.The effects of ingested ammonia are not well studied, but

are a function of body size, intake rate, and physiology.Ingested ammonia has been reported as toxic to humans atabout 27mgN–NH3/kg body weight (World HealthOrganization 2003). Water consumption rates from theliterature (World Health Organization 2003) were mass-normalized, and from these rates the proportions of toxicammonia intakes were calculated for wildlife species, basedon the human data. We used body mass (kg) from theliterature and our maximum measure of ammonia concen-tration at 55mg/L N–NH3 to calculate the equivalentproportion of ammonia relative to a human toxic dose

Figure 1. Natural tinajas (left photo credit J. Drake) and artificial catchments (right photo credit J. Goetting) both provide water for wildlife and humans in theSonoran Desert.

Figure 2. The frequency of the number of species of amphibian tadpoles and the number of species of dragonflies that occurred at tinajas (natural and modifiedrock pools) and constructed water catchments across 7 mountain ranges in southwestern Arizona, USA. Species richness of amphibians (ordinal logisticregression: x2¼ 9.3; df¼ 1, P¼ 0.002) and dragonflies (x2¼ 19.2; df¼ 1, P< 0.001) were significantly higher in tinajas.

Griffis-Kyle et al. � Water Quality: Hidden Danger in Desert Catchments 149

(Table 1). We do not know how elevated ammonia mightaffect fetuses or nursing young, but in general pregnant andlactating females have water turnover rates 40–50% higherthan non-lactating animals (Cain et al. 2006).Because ammonia affects neurological function and

can expedite dehydration in humans (World HealthOrganization 2003), water quality in artificial catchmentsmay play a role in human mortality across the United States–Mexico border. Despite a >50% decrease in Mexicanimmigration between the periods of 2000–2004 (3 million)and 2005–2010 (1.4 million), the relative proportion ofbodies recovered more than doubled from 0.03% to 0.08%(Arizona Recovered Human Remains Project, retrievedon Jan 29, 2013; http://derechoshumanosaz.net/projects/arizona-recovered-bodies-project/). This mortality is notwholly due to increased border violence, because only 4% ofthe bodies recovered in 2012 had signs of bullet wounds.Increased patrolling of the United States–Mexico bordermay have increased the detection rate of deceased humansand thus may account for a portion of the reported increase.However, other factors may play a role in human mortality,including consumption of poor-quality water exacerbatingdehydration in already physiologically stressed individuals.

MANAGEMENT IMPLICATIONS

Our results should concern institutions that manage humanmigration, wildlife, and biodiversity. Ammonia in artificialwater sources may have already affected the lives and healthof a host of organisms: invertebrates, wildlife, and people.We should test and identify novel solutions to manage thisproblem. Potential solutions may include modifications tocatchment design, periodic cleaning of organic debris fromthe catchments, or oxygenating the water to enhancenitrification if the necessary bacteria are present. We hopeour study improves the management of wildlife populationsand the survival of humans traveling in this arid landscape.

ACKNOWLEDGMENTS

We thank the 56th Range Management Office of Luke AirForce Base for funding and for help coordinating field

schedules with military maneuvers. We also thank J.Goetting, J. Drake, K. Smith, V. Marshall, and T. Calvertfor their efforts in the field. This is manuscript number T-9-1245 of the College of Agricultural Sciences and NaturalResources, Texas Tech University.

LITERATURE CITEDAnthonisen, A. C., R. C. Loehr, T. B. S. Prakasam, and E.G. Srinath. 1976.Inhibition of nitrification by ammonia and nitrous acid. Journal of theWater Pollution Control Federation 48:835–852.

Broyles, B. 1995. Desert wildlife water developments: questioning use in theSouthwest. Wildlife Society Bulletin 23:663–675.

Cain, J. W., P. R. Krausman, S. S. Rosenstock, and J. C. Turner. 2006.Mechanisms of thermoregulation and water balance in desert ungulates.Wildlife Society Bulletin 34:570–581.

Camargo, J. A., and A. Alonso. 2006. Ecological and toxicological effects ofinorganic nitrogen pollution in aquatic ecosystems: a global assessment.Environment International 32:831–849.

Elder, J. B. 1954. Notes on summer water consumption by desert mule deer.Journal of Wildlife Management 18:540–541.

Fox, L. M. 1997. Nutritional content of forage in Sonoran pronghornhabitat, Arizona. Thesis, University of Arizona, Tucson, USA.

Harrington, R., N. Owen-Smith, P. C. Viljoen, H. C. Biggs, D. R. Mason,and P. Funston. 1999. Establishing the causes of the roan antelope declinein the Kruger National Park, South Africa. Biological Conservation90:69–78.

Hervert, J. T., and P. R. Krausman. 1986. Desert mule deer use of waterdevelopments in Arizona. Journal of Wildlife Management 50:670–676.

James, C. D., J. Landsberg, and S. R. Morton. 1999. Provisioning ofwatering points in the Australian arid zone: a review of effects on biota.Journal of Arid Environments 41:87–121.

Jocque, M., K. Martens, B. Riddoch, and L. Brendock. 2006. Faunistics ofephemeral rock pools in southeastern Botswana. Archiv Fur Hydro-biologie 165:415–431.

Relyea, R. A., R. K. Lawrence, and S. Demarais. 2000.Home range of desertmule deer: testing the body-size and habitat productivity hypotheses.Journal of Wildlife Management 64:146–153.

Richmond, C. R., W. H. Langham, and T. T. Trjillo. 1962. Comparativemetabolism of tritiated water by mammals. Journal of Cellular andComparative Physiology 59:45–53.

Robinson, S., and A. R. Robinson. 1954. Chemical composition of sweat.Physiological Reviews 34:202–220.

Rosenstock, S. S., J. T. Hervert, V. C. Bleich, and P. R. Krausman. 2001.Muddying the water with poor science: a reply to Broyles and Cutler.Wildlife Society Bulletin 29:734–738.

Rosenstock, S. S., M. J. Rabe, C. S. O’Brien, and R. B. Waddell. 2004.Studies of wildlife water developments in southwestern Arizona: wildlifeuse, water quality, wildlife disease, wildlife mortalities and influences on

Table 1. The estimated daily toxic dose of ammonia for select species of animals known to drink from the wildlife catchments in the Sonoran Desert ofArizona, USA.

SpeciesMass(kg)

Lethal intakebased on bodysize (g/day)

Mass-normalizeddaily water

need (L/day/kg)

Proportion ofhuman toxicconcentration

based on massa (%)

Desert bighorn 52 F, 77 Mb 1.4 0.040c 8–12Sonoran pronghorn 54–64d,e 1.5 0.076e 16Desert mule deer 59.5f 1.5 0.119g 25Human 68–81h 1.9 0.138i 29

a World Health Organization (2003).b Russo (1956).c Turner (1970).d Richmond et al. (1962).e Fox (1997).f Relyea et al. (2000).g Richmond et al. (1962), Elder (1954), Hervert and Krausman (1986).h Walpole et al. (2012).i Robinson and Robinson (1954).

150 Wildlife Society Bulletin � 38(1)

native pollinators. Arizona Game and Fish Department, Research BranchTechnical Guidance Bulletin No. 8, Phoenix, USA.

Russo, J. P. 1956. The desert bighorn sheep in Arizona. Arizona Game andFish Department, Wildlife Bulletin 1, Phoenix, USA.

Simpson, N. O., K. M. Stewart, and V. C. Bleich. 2011. What have welearned about water developments for wildlife? Not enough! CaliforniaFish and Game 91:190–209.

Turner, J. C. 1970. Water consumption of desert bighorn sheep. DesertBighorn Council Transactions 14:189–197.

Walpole, S. C., C. Prieto-Merino, P. Edwards, J. Cleland, G. Stevens, and I.Roberts. 2012. The weight of nations: an estimation of adult humanbiomass. BMC Public Health 12:439.

World Health Organization. 2003. Ammonia in drinking-water. Back-ground document for development of WHO guidelines for drinking-water quality. WHO/SDE/WSH/03.04/01, Geneva, Switzerland.

Associate Editor: Brennan.

Griffis-Kyle et al. � Water Quality: Hidden Danger in Desert Catchments 151