Invasive alien species (IAS) turtles pose big environmental problem. They compete for food and territory to autochthonous species, i.e. strictly protected European pond turtle (Emys orbicularis). They can carry or transfer pathogens for other reptiles, amphibians, fish, and humans.
The objectives of the study was evaluation of IAS turtles population size captured from natural environment in Lublin area (eastern Poland) and assessment of health status and condition of IAS turtles in Polish climate conditions. Trapping with floating platforms with pitfall cages and ramps (Epicrates Turtle Traps - ETT) was held for three years (2015-2017) from April to October. Some turtles were delivered by citizens (i.e. fishermen). All captured animals were submitted to clinical examination and measurements. Species, sex, weight, and size of an individual was recorded. Condition was quantified with numerical index (1 – 3) for locomotion, aggressiveness, muscle strength. Common physical examination questionnaire was developed to harmonise data collection and score parameters by quantitative (absent – present) or semi-quantitative way (bad – poor – intermediate – good – very good;) to asses clinical status of head, eyes, ears, mouth, nares, integument, limbs, prefemoral fossae, tail, cloaca, and shell. The score for no clinical abnormalities reached 10 points. Detailed description and photo documentation of findings was conducted.
Majority of 120 turtles captured represented subspecies of Trachemys scripta: red-eared slider (Trachemys scripta elegans; n = 73), Cumberland slider (Trachemys scripta troosti; n = 11), yellow-bellied slider (Trachemys scripta scripta; n = 31). The remaining chelonians were false map turtle (Graptemys pseudogeographica; n = 3) and single common snapping turtle (Chelydra serpentina) and hybrid of different slider species. Seventy-eight turtles (65%) were female and 42 (35%) males.
Twenty-eight turtles (23,3%) showed no clinical signs (10/10 score). The lowest score 5/10 was achieved in single individual (0,8%). Two individuals were found dead prior examination: one collected dead from ETT, the other deceased during quarantine. Abnormalities were mostly observed in carapace (51,6 %) and plastron (37,5 %): metabolic disorders, excess scutes, and erosions were mainly seen. Skin disorders were found in 28,3% of turtles. Altogether, different forms of Septicemic Cutaneous Ulcerative Disease (SCUD) might have been assumed. Several animals (10,8%) showed problems with eyes (clarity and brightness, conjunctiva, cornea), and mouth (peak, mucosa, tongue, glottis, Eustachian tubes abnormalities). The other symptoms were affected limbs/joints (8,3%) and respiratory tract disease (nares exudation; 3,3%). No cloaca or ears pathology or ectoparasites were noted. Missing digits or effect of aggressive conflicts or predator attacks were seen. With few exceptions the turtles were in perfect condition: aggressive, uncooperative and opposing strongly during examination.
Our study shows that captured invasive alien turtles show generally good health status and condition as well as they strongly adopted to non-autochthonous natural environment of eastern Poland.
This work was supported by the National Science Centre project “Invasive turtle species as a source and vector of animal and human pathogens” (Grant No. 2013/11/B/NZ7/01690).
Topics: Management of Human-Wildlife Conflicts: “Other” Species in Europe
