Raimon Guitart

Marine debris ingestion in loggerhead sea turtles, Caretta caretta, from the Western Mediterranean

Marine debris represents an important threat for sea turtles, but information on this topic is scarce in some areas, such as the Mediterranean sea. This paper quantifies marine debris ingestion in 54 juvenile loggerhead sea turtles (Caretta caretta) illegally captured by fishermen in Spanish Mediterranean waters. Curved carapace length was measured, necropsies were performed and debris abundance and type was recorded. Different types of debris appeared in the gastrointestinal tract of 43 turtles (79.6%), being plastics the most frequent (75.9%). Tar, paper, Styrofoam, wood, reed, feathers, hooks, lines, and net fragments were also present. A regression analysis showed that the volume of debris increased proportionally to the size of the turtles. The high variety of debris found and the large differences in ingestion among turtles indicated low feeding discrimination of this species that makes it specially prone to debris ingestion. Our data suggest that more severe control of litter spills and greater promotion of environmental educational programmes are needed in the Western Mediterranean.

A review of the effects of agricultural and industrial contamination on the Ebro Delta Biota and wildlife

The Ebro delta (NE Spain) is a 320 km2 wetland area ofinternational importance for conservation. The area is devotedto rice farming and receives large amounts of pesticides.Industrial pollutants are also carried to the delta by the river.The information accumulated during the last 25 year on the effectof such pollution on the biota is reviewed in order to identifythe existing gaps and needs for management. Organochlorinepesticides were legally used until 1977, which has resulted inthe widespread presence of these compounds in the Ebro deltabiota. Lethal, sublethal or other detrimental effects of thesepesticides on wildlife in the area were poorly investigated, butnegative effects on the reproduction of ducks and herons werereported. Nowadays, polychlorinated biphenyls (PCBs) are themain responsible of organochlorine pollution in the area:concentrations in biota samples are higher than levels observedin nearby coastal areas, as a result of the significant PCBinputs by the river which, in 1990, were evaluated at 126 kgyr-1. The massive use of herbicides is thought to havecontributed to the elimation of macrophyte vegetation in thelagoons during the eighties, which had strong consequences ondiving ducks and coot populations. Weed control is also relatedto the loss of biodiversity held by rice fields. The massive andinadequate use of organophosphorus and carbamate pesticides(involving more than 20 000 t yr-1) has produced somewaterbird mortality events, and may have direct and indirecteffects on other non-target organisms. The accumulation in thesoil of lead pellets used in waterfowl shooting is estimated tokill some 16 300 waterbirds in the Ebro delta every year.

Animal poisoning in Europe. Part 2: Companion animals

This is the second in a series of three review articles on animal poisoning in Europe and focuses on cases in pet animals and horses in five European countries (Belgium, France, Greece, Italy and Spain) reported over the last decade. In the participating countries, dogs were the most commonly poisoned species, particularly younger animals. The majority of cases in companion animals resulted from exposure to insecticides, although rodenticides (especially anticoagulants and strychnine) posed a significant risk. In all five countries, horses and cats appeared to be more susceptible to plant toxins. Intoxications with herbicides, metals, household products and drugs for veterinary and human use were reported sporadically. The review demonstrates the importance of increased awareness so as to minimise poisoning episodes and emphasises the need to establish a European system for the recording of poisoning data.

Animal poisoning in Europe. Part 3: Wildlife

This review article is the third in a series on animal poisoning in Europe and represents a collation of published and non-published wildlife poisoning data from Belgium, France, Greece, Italy and Spain over the last 10 years. Birds, particularly waterfowl and raptors, were more commonly reported as victims of poisoning than wild mammals. In addition to specific but important toxicological disasters, deliberate primary or secondary poisonings are of concern to all countries. Metals (particularly lead arising from sporting/hunting activities) and pesticides (mainly anticholinesterases and anticoagulants) are frequent causes of poisoning, and often have fatal consequences. A more unified and consistent approach throughout European countries to improve the reporting and the analytical confirmation of wildlife poisoning would help to reduce the number of cases of malicious or negligent animal poisoning.

Requirement for a standardized nomenclature criterium for PCBs : computer-assisted assignment of correct congener denomination and numbering

Abstract Due to the great number of congeners, the use of the correct nomenclature for PCBs is a difficult task, and unfortunately errors in the assignment of chemical denominations are not unusual. We suggest in this paper to correctly apply the rules initially introduced by Ballschmiter and Zell in 1980, which differ from those of the IUPAC. A simple algorithm in BASIC was created to help researchers in this field to denominate all the 209 congeners by their correct Ballschmiter and Zell and/or IUPAC systematic names.

Lead shot pellets in the Ebro delta, Spain: Densities in sediments and prevalence of exposure in waterfowl

Lead (Pb) poisoning has been found to be a serious problem for waterfowl in some southern European countries, but few studies have been conducted in Spain. In order to obtain these data, studies were made in the Ebro delta, a Spanish Ramsar site, during 1992 and 1993. Lead shot densities in the first 20 cm of sediment ranged from < 8 900 to 2 661 000 shot ha(-1). A similar proportion of birds had lead shot in the gizzard and elevated liver lead (> 5 microg g(-1) DW) concentrations. Northern pintail and common pochard (both with declining populations in Europe) showed the highest levels of shot ingestion, with 70.8 and 69.2%, respectively. Body condition index in the northern pintail was negatively correlated with the number of pellets in the gizzard and liver Pb concentration. Levels of exposure were higher than in other northern countries of the western Palearctic flyway, where lead shot have been banned recently.

Lead poisoning in waterfowl from the Ebro Delta, Spain: Calculation of lead exposure thresholds for mallards

Lead poisoning in waterfowl was investigated during 1991/92 at the Ebro Delta Natural Park. Sediment examination showed a lead shot concentration available to waterfowl ranging from 60,149 to 544,748 shot pellets/ha in some zones. Examination of gizzards from 108 bird carcasses confirmed that four different species had ingested lead shot. To establish prevalence values for waterfowl, 50 ducks, mainly mallards (Anas platyrhynchos) (n=40), were captured. Examination of the gizzard contents revealed that 25% of the mallards had ingested lead pellets. Lead concentration in liver and kidneys was determined by atomic absorption spectrometry, and the diagnostic concentration values for both of the organs were studied. The mallard population was divided into two groups, based on the presence or absence of lead shots in their gizzards. After a probit transformation of data, threshold values were 1.5 μg/g WW in liver and 3.0 μg/g WW in kidneys. The results derived from lead concentrations and gizzard examination showed that 27% of the mallards in the winter period were poisoned, which represents about 10,000 individuals of a population of 36,500 mallards in the Ebro Delta.

Animal poisoning in Europe. Part 1: Farm livestock and poultry.

The lack of a reference Veterinary Poison Control Centre for the European Union (EU) means that clinicians find it difficult to obtain information on poisoning episodes. This three-part review collates published and unpublished data obtained from Belgium, France, Greece, Italy and Spain over the last decade in order to provide a broader toxicoepidemiological perspective. The first article critically evaluates the national situation in the five European countries and concludes that information for livestock and poultry is limited and fragmentary compared to other animal groups. The analysis has revealed that clinical cases of poisoning are only occasionally studied in depth and that cattle are the species most frequently reported. Several plants and mycotoxins, a few pesticides and metals, together with contaminants of industrial origin, such as dioxins, are responsible for most of the recorded cases.

Determinants of lead shot, rice, and grit ingestion in ducks and coots.

We investigated the relationships between lead shot ingestion, grit size selection, bill morphology, and diet in a community of 8 duck species and common coot (Fulica atra) wintering in the Ebro Delta, Spain. There were no intraspecific differences related to sex or age in grit composition, lead shot, and rice-grain ingestion. Strong interspecific differences were recorded for all these variables and for the density of bill lamellae. The proportion of grit of size >1 mm (especially >2-3 mm) was positively correlated with the prevalence of lead shot ingestion, as well as with rice ingestion. Rice ingestion was also positively correlated with the prevalence of lead shot ingestion. Those duck species feeding on rice had larger grit and higher prevalences of lead shot than herbivorous species. Contrary to the predictions of a straining model for food or grit ingestion, lamellar density did not explain interspecific differences in grit selection, rice ingestion, or prevalence of lead shot ingestion. These findings contradict previous claims in the literature, and suggest that mechanisms other than straining are used by ducks for grit selection and lead shot ingestion.

Lead shot ingestion by marsh harriers Circus aeruginosus from the Ebro delta, Spain

Breeding marsh harriers disappeared from the Ebro delta in the 1980s. Although marsh harrier breeding populations have recently increased in other wetlands of NE Spain, recolonization by breeding birds has not been observed in the Ebro delta, despite the fact that it is an important wintering area for the species. Lead (Pb) poisoning in marsh harriers, a problem described in other European wetlands, has been studied as a possible cause of this breeding impairment. Around 11% of harrier pellets (mainly with duck remains) contained Pb shot, and 52.5% of marsh harriers had blood [Pb] higher than 200 ng ml−1. Maximum values for both parameters occurred in the middle of the hunting season. Blood [Pb] of wing-tagged marsh harriers classified as wintering birds was higher than those classified as migrant birds, and Pb levels decreased at the end of the hunting season. Body condition was not affected by blood [Pb], and none of the marsh harriers found dead had died of Pb poisoning. Birds with blood [Pb] higher than or equal to 601 ng ml−1 returned to the Ebro delta in the next winter in a lower proportion (1/3) than birds with blood [Pb] lesser than or equal to 200 ng ml−1 (6/6), although this difference was not statistically significant (P=0.083). Pb poisoning may affect populations of wintering marsh harriers, but other ecological and behavioural aspects have to be considered as well to explain the lack of breeding recolonization of the Ebro delta. ©