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Kirke A. King

Publications and source records attributed to Kirke A. King.

6 recordsLinked to original sources
USGS2002

Contaminants without borders: A regional assessment of the Colorado River Delta ecosystem

The Colorado River Delta Region (CRDR) is comprised of large agricultural areas in the U.S. (Imperial and Yuma districts) and Mexico (Mexicali and San Luis districts), the Salton Sea, and the Lower Colorado River from southern Arizona to the Gulf of California (Valdés-Casillas et al., 1998). Before agricultural development, the lower delta comprised large riparian and wetland areas (Sykes, 1937; Glenn et al., 1999). Currently, most water from the Colorado River below Imperial Dam is used for irrigation in California and Mexico, and only remnants of the former CRDR wetlands remain. However, the Cienega de Santa Clara and the Rio Hardy wetlands (Figure 111.1) provide important habitat for many resident and migratory birds, including endangered species such as the desert pupfish (scientific names are provided in Table 111.1) and the Yuma clapper rail (Abarca et al., 1993; Mellink et al., 1997). Detailed descriptions of the CRDR and its wetlands are provided elsewhere (Sykes, 1937; Glenn et al., 1995; 1999; Friederici, 1998; Valdés-Casillas et al., 1998).

California↗
USGS1991

Effects of mercury, selenium, and organochlorine contaminants on reproduction of Forster's terns and black skimmers nesting in a contaminated Texas bay

Mean mercury (0.40 μg/g), and geometric mean DDE (1.6 μg/g) and polychlorinated biphenyl (PCB) (2.3 μg/g) concentrations in Forster's tern ( Sterna forsteri ) eggs from Lavaca Bay were higher than those in tern eggs from a reference area in San Antonio Bay, but residues were not correlated with hatching success. Nest success was similar between bays. Selenium levels in Lavaca Bay tern eggs (0.71 μg/g) were also comparable to those in eggs from the reference area (0.68 μg/g). Clutch size (3.1 to 3.4) of Lavaca Bay black skimmers ( Rynchops niger ) was no different than that (3.4) at a reference colony near Laguna Vista. Nest success was similar among three Lavaca Bay colonies, but success was lower at one Lavaca Bay colony (40%) than at Laguna Vista (65%). Mean mercury (0.46 μg/g) and selenium (0.75 μg/g) concentrations in skimmer eggs from Lavaca Bay were higher than those (0.19, 0.33 μg/g) from Laguna Vista; however, concentrations of neither contaminant were related to hatching success. DDE concentrations in Lavaca Bay skimmer eggs (3.4 μg/g) were similar to those from Laguna Vista (3.2 μg/g) and DDE was negatively correlated with hatching success. PCBs were higher in eggs from Lavaca Bay (1.3 μg/g) than Laguna Vista (0.8 μg/g). Organochlorine and metal contaminants in most eggs were below embryotoxic levels. Eggshell thinning in Forster's terns (7%) and black skimmers (5%) was below that associated with lowered reproduction. DDE and PCBs were detected in 9 Caspian tern ( S. caspia ) eggs; maximum concentrations were 4.7 and 5.4 μg/g. Caspian tern and least tern ( S. albifrons ) eggs contained low (⩽0.9 μg/g) concentrations of mercury and selenium.

Texas↗
USGS1986

Population trends, reproductive success, and organochlorine chemical contaminants in waterbirds nesting in Galveston Bay, Texas

The effects of environmental contaminants on the reproductive success of olivaceous cormorants ( Phalacrocorax olivaceus ), laughing gulls ( Larus atricilla ), and black skimmers ( Rhynchops niger ) nesting in Galveston Bay, Texas were investigated from 1980 through 1982. Populations of cormorants and gulls have remained stable in recent years, but skimmer numbers may have declined. Cormorants produced 1.9 to 2.8 young per pair in nests that remained active throughout the season. Gull and skimmer reproduction was seriously limited by storms and predation. DDE and polychlorinated biphenyl (PCB) residues in carcasses and eggs generally were below levels associated with chronic poisoning and reproductive problems in most species of birds. Possible exceptions were four black skimmer carcasses with DDE concentrations that ranged from 20 to 92 Μ g/g and one olivaceous cormorant carcass with 20 Μ g/g DDE. The generally low levels of dieldrin, chlordane, HCB, toxaphene, and heptachlor epoxide were below those know to affect avian reproduction and survival. Mean DDE residues in cormorant and gull eggs were less than 1.8 Μ g/g. The mean DDE residue in skimmer eggs was less than 3.3 Μ g/g; 12% of the skimmer eggs contained at least 12 Μ g/g DDE, a level known to cause reproductive problems in some avian species. DDE in the eggs of all species declined from 1.5- to 7-fold over the past decade. Polychlorinated biphenyl was detected in all gull and skimmer eggs and in 90% of the cormorant eggs. Residues of PCB in cormorant and skimmer eggs in 1980–82 were lower than in 1970, but the frequency of occurrence in gull eggs increased. Polychlorinated styrenes were recovered in 45% of the cormorant carcasses at levels below 1 Μ g/g. Eggshell thicknesses in all three species were similar to those of eggshells collected before the widespread use of DDT.

Texas↗
USGS1977

Ticks as a factor in nest desertion of California brown pelicans

In summary, our observations suggest that O. denmarki may be an important environmental factor influencing the distribution and success of Brown Pelican nests in the Gulf of California. More information on these relationships may be unobtainable without seriously disturbing and destroying large numbers of nests.

The Condor↗