Analysis of antropogenic waste found in the digestive tract of green turtles (Chelonia mydas).

Abstract

Currently two thirds of the population lives in coastalregions. In Santos region, the population is about 1.6 million permanentresidents , more of the population resort . The advance over these areaspromotes increased amount of refuse where the main problem is the improperdisposal of these products anthropogenic , which become a threat and achallenge mainly due to the persistence time of the components in theenvironment, in particular plastics , which were perceived in studies since the80s due to the high strength and durability . The green turtle ( C. mydas ) is a species classified asendangered by IUCN since 1982 as suffering from human impacts , including theanthropogenic inputs due to its coastal habits. The ingestion of these residuesmay obstruct the handling of the animal, directly causing the death of , orcause sub-lethal effects such as damage to the walls of the gastrointestinaltract , reduced nutritional gain , increased time of food in the compartmenttract and altered buoyancy by the accumulation of gases in the intestine . Thisstudy aims to analyze the types and quantities of waste anthropogenic found inthe gastrointestinal system of 47 carcasses of juvenile green turtles rescuedand necropsied in the beaches of Santos between January 2010 and July 2011. Theanthropogenic contributions found in gastrointestinal contents of theseindividuals were referred to the scientific laboratory of Santa CeciliaUniversity , where he was triaged metal , paper, cloth (cotton) , syntheticpolymers and copolymers (plastic / nylon / rubber / foam / styrofoam ). Anthropogenicwaste were weighed on an analytical balance and measure the volumetricmeasuring cylinders with the principle of Archimedes  The average volume of waste found was 6.85 ±7.0 cm³ (1 – 120) and mean weight was 2.7 ± 3.5g ( 0.02 to 12.9 ). The predominantanthropogenic material was the plastic found in 97.87 % ( 46/47 ) of thesamples analyzed . Fragments found 42.87 % ( 1772/4133 ) were rigid plasticsand 52.31 % ( 2162/4133 ) of pliable plastic weighing 213g, 37g e 76.8grespectively. Monofilament nylon represent 41.35%  (894/2162 ) of total waste plastics pliable ,found in 78.72% ( 37/47 ) of animals sampled. .The other synthetic materials such as rubbers , foams and styrofoam had lowincidence of 3.8 % ( 157/4133 ) as well as the cotton fabric with 1.6 % (66/4133 ) , which agrees with previous studies and suggests a negativeinteraction of C. mydas withanthropogenic debris plastic in the region of Santos