title: Influence of contamination by organochlorine pesticides and polychlorinated biphenyls on the breeding of the spanish imperial eagle (Aquila adalberti).
abstract: We evaluated temporal and regional trends of organochlorine (OC) pesticide (including polychlorinated biphenyl [PCB]) levels in eggs of the Spanish Imperial Eagle (Aquila adalberti) collected in Spain between 1972 and 2003. Levels of p,p'-dichlorodiphenyldichloroethylene (DDE) and PCBs varied significantly (p = 0.022) among regions (central, western, and Doñana), being higher in Doñana than in the central and western populations (DDE: 1.64 +/- 5.56, 0.816 +/- 1.70, and 1.1 +/- 2.66 microg/g, respectively; PCBs: 1.189 +/- 5.0, 0.517 +/- 1.55, and 0.578 +/- 1.75 microg/g, respectively). Levels of DDE decreased with time, but a significant interaction was observed between region and time. In Doñana, egg volume and breadth as well as Ratcliffe Index were significantly lower after DDT use (p = 0.0018) than during the pre-DDT period (p = 0.0018); eggs were significantly smaller overall than in the other two regions (p = 0.04) and were smaller when DDE levels increased, even when controlling for regional differences (p = 0.04). Productivity in Doñana was significantly lower than in the other regions (p < 0.001). Clutch size in Doñana varied according to DDE concentrations (p = 0.01), with the highest DDE concentrations found in clutches consisting of one egg. When considering eggs with DDE levels greater than 3.5 microg/g, a significant effect of DDE on fertility was found (p = 0.03). Clutches with DDE levels greater than 4.0 microg/g had a higher probability of hatching failure (p = 0.07) and produced fewer fledglings (p = 0.03). If we consider 3.5 microg/g as the lowest-observable-adverse-effect level, the proportion of sampled clutches that exceeded that level in Doñana (29%) was significantly higher than in other regions (p < 0.001). These eggs showed a mean percentage of thinning of 16.72%. Contamination by OCs, mainly DDE, could explain, at least in part, the low productivity of the Spanish Imperial Eagles in Doñana.
authors.affiliation: Laboratorio Forense de Vida Silvestre, Edificio Alba, Las Matas, Madrid, Spain. lfvs@arrakis.es
authors.forename: Mauro
authors.initials: M
authors.lastname: Hernández
authors.forename: Luis M
authors.initials: LM
authors.lastname: González
authors.forename: Javier
authors.initials: J
authors.lastname: Oria
authors.forename: Roberto
authors.initials: R
authors.lastname: Sánchez
authors.forename: Beatriz
authors.initials: B
authors.lastname: Arroyo
mesh_terms: D000818:Animals; D001947:Breeding; D020307:Eagles / Q000502:physiology*; D004528:Egg Shell / Q000737:chemistry; D004785:Environmental Pollutants / Q000032:analysis / Q000633:toxicity*; D006843:Hydrocarbons, Chlorinated / Q000032:analysis / Q000633:toxicity*; D010575:Pesticides / Q000032:analysis / Q000633:toxicity*; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000633:toxicity*; D011158:Population Growth; D012098:Reproduction / Q000187:drug effects* / Q000502:physiology; D013030:Spain; D013997:Time Factors
chemical_list: D004785:Environmental Pollutants; D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D011078:Polychlorinated Biphenyls