Microcontaminants and reproductive impairment of the Forster's tern on Green Bay, Lake Michigan-1983

Abstract

For the 1983 nesting season, Forster's tern (Sterna forsteri) reproductive success was significantly impaired on organochlorine contaminated Green Bay, Lake Michigan compared to a relatively uncontaminated inland location at Lake Poygan, Wisconsin. Compared with tern eggs from Lake Poygan, eggs from Green Bay had significantly higher median concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), other polychlorinated dibenzo-p-dioxins (PCDDs), total polychlorinated biphenyls (PCBs), total (three congeners) non-ortho, ortho' PCBs, five individual PCB congeners known to induce aryl hydrocarbon hydroxylase (AHH) and several other organochlorine contaminants. Conversions of analytical concentrations of TCDD and PCB congeners based on relative AHH induction potencies allowed for estimation of total 2,3,7,8-TCDD equivalents. Two PCB congeners, 2,3,3',4,4'- and 3,3',4,4',5-pentachlorobiphenyl (PeCB) accounted for more than 90% of the median estimated TCDD equivalents at both Green Bay and Lake Poygan. The median estimated TCDD equivalents were almost 11-fold higher in tern eggs from Green Bay than in eggs from Lake Poygan (2175 and 201 pg/g). The hatching success of Green Bay sibling eggs from nests where eggs were collected for contaminant analyses was 75% lower at Green Bay than at Lake Poygan. Hatchability of eggs taken from other nests and artificially incubated was about 50% lower for Green Bay than for Lake Poygan. Among hatchlings from laboratory incubation, those from Green Bay weighed approximately 20% less and had a mean liver weight to body weight ratio 26% greater than those from Lake Poygan. In both field and laboratory, mean minimum incubation periods were significantly longer for eggs from Green Bay compared to Lake Poygan (8.25 and 4.58 days, respectively). Mean minimum incubation time for Green Bay eggs in the field was 4.37 days longer than in the laboratory. Hatchability was greatly improved when Green Bay eggs were incubated by Lake Poygan adults in an egg-exchange experiment, but was sharply decreased in Lake Poygan eggs incubated in Green Bay nests. Nest abandonment and egg disappearance were substantial at Green Bay but nil at Lake Poygan. Thus, not only factors intrinsic to the egg, but also extrinsic factors (parental attentiveness), impaired reproductive outcome at Green Bay. The epidemiological evidence from this study strongly suggested that contaminants were a causal factor. AHH-active PCB congeners (intrinsic effects) and PCBs in general (extrinsic effects) appeared to be the only contaminants at the concentrations measured in eggs, capable of producing the effects that were observed at Green Bay.

Reduced breeding success of Cormorants (Phalacrocorax carbo sinensis) in relation to persistent organochlorine pollution of aquatic habitats in The Netherlands

“…the attentiveness at the nest of the birds (Peakall & Peakall, 1973;Peakall & Fox, 1987;Scholten et al, 1989). This is difficult to separate from egg mortality caused by contaminant concentrations, without behavioural observations in the colony or egg change experiments between colonies (Kubiak et al, 1989). Both methods were not used in the present study.…”

“…Only few comparative examples are available, mostly applying to a two-group comparison. For example in Forster's terns (Sterna firsteri), Kubiak et al (1989) found 1 lfold higher TCDD equivalents (in which two PCB congeners accounted for more than 90% of the total) in eggs from a colony with a low hatching success in a heavily contaminated area as compared to eggs from a colony in a relatively clean area where reproduction was normal. In this study, a significant correlation between effect and concentration was found for all six non-planar PCBs analysed, although the correlation coefficients were rather low.…”

“…In aquatic ecosystems especially, fish eating birds and mammals have been the conspicuous victims of contamination with DDT (and related compounds like DDE), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Studies on gulls, terns, cormorants and raptors have linked (some of) these contaminants with reproductive failure through eggshell thinning and subsequent breaking of eggs (Ratcliffe, 1967(Ratcliffe, , 1970 Lundholm, 1987), mortality of embryos and little chicks (Fox, 1976;Morris et al, 1976;Vermeer 8e Peakall, 1977;Gilbertson, 1983;Kubiak et al, 1989), and m,orphological aberrations in chicks (Hays & Risebrough, 1972;Gochfeld, 1975;Gilbertson et al, 1976). The combination of the latter two types of effects has been reviewed extensively and named Great Lakes Embryo Mortality, Edema and Deformities Syndrome (GLEMEDS) (Gilbertson et al, 1991).…”

Toxic and biochemical effects of 3,3′,4,4′-tetrachlorobiphenyl (CB-77) and clophen A50 on eider duckling (Somateria mollissima) in a semi-field experiment

“…This effect was not found for the C1oA50-200 mg kg -1 group. PCBs have been shown to influence bird behaviour much as parental attentiveness (Kubiak et al, 1989;McArthur et al, 1983), courtship behaviour (Tori & Peterle, 1983) and avoidance behaviour (Kreitzer & Heinz, 1974). The mechanism through which behaviour is influenced is not yet clear.…”

“…In fish-eating birds, exposure to PCBs and related compounds has been associated with effects such as impaired reproduction (Hoffman et al, 1986(Hoffman et al, , 1987Kubiak et al, 1989;Van den Berg et al, 1993), morphological abnormalities (Hoffman et al 1986(Hoffman et al , 1987, thymus atrophy and immunotoxicity (Nikolaidis et al, 1988;Andersson et al, 1991), hypovitaminosis A and/or hypothyroidy (Moccia et al, 1986;Spear et al, 1989;Van den Berg et al, 1993), behaviourial changes (Kubiak et al, 1989;McArthur et al, 1983;Tori & Peterle, 1983), and loss of body weight (Koeman et al, 1973;Gilbertson, 1989). Most of these studies are, however, fieldwork in which it is impossible to make a distinction between effects caused by PCBs and those caused by other substances such as polycyclic aromatic hydrocarbons (PAHs).…”