WILD DELTA/ The otter, a protected species returns to the Danube Delta

Autor: George Traicu
Publicat: 07-08-2022 10:54

The otter, a protected species, whose decline was evident in the second part of the last century, is now found in almost all the Danube Delta, according to the data provided to AGERPRES by the Danube Delta National Institute for Research and Development (INCDDD).

It is said that the otter was a beautiful girl who did not want to marry the one her parents wanted her to, so that she was punished not to stay in the water all the time, but also on land.

According to INCDDD, the presence of the otter, included in the Red List of strictly protected species, depends on the existence of feed resources. In Romania, the species has a wide spread, especially in the lakes and valleys of large waters, but especially in the ponds of the Danube Delta. Despite this, the otter population declined from 2,050 individuals in 1950 to 1,550 in 1991.

"In the Danube Delta Biosphere Reserve (RBDD), the otter was observed on all over the surface, in the freshwater areas, including in anthropogenic areas: Tulcea city port, agri-forest-fishing facilities and near the hearths of the village settlements. In this territory, it is estimated that there is the majority of the population of the species at the national level. Of all the mammal species of community interest in RBDD, the otter is the most often observed. Between 2010 and 2021, the otter was observed in all aquatic ecosystems on the territory of RBDD, including in anthropogenic areas," a paper signed by the specialists of INCDDD reads.

Most otters were recorded in the Sontea - Furtuna area and in the Razim - Sinoie lagoon system.

"The otter is mainly solitary, with males and females joining only during mating. They are territorial animals, marking the borders of the individual territory with leaves and a thick, sticky secretion produced by the gland. The territory of an individual has an interval of 7-15 linear kilometers. Males have larger territorial ranges than females, the territory of one male overlapping that of several females, but not that of other males. The territories of the females do not overlap, the otters displaying territorial aggression towards the otters of the same sex. The population density is usually about one otter per kilometer of navigable squat, but may be less than an otter 5 kilometers per stream. Males seem to form a dominant hierarchy, the most dominant male occupying the most favorable areas," the specialists of INCDDD say.

"The enemies of the species are man and dog. The otter is hunted especially in winter, at the ice-fishing. Similarly, dogs are specially trained to kill otters; subsequently, the dogs act in this regard and without the exhortation of the owners. Young individuals are also killed by unrestrained dogs. Sometimes, otters are shot or captured with traps and in ponds," the specialists of INCDDD say.

Among the main causes of the numerical change are the pollution of the waters with pesticides and fertilizers for agriculture, the degradation of habitats and the hunting for fur, and among the most important protection measures necessary are the combating of poaching and the limitation of the number of wandering dogs, as well as the limitation of the nautical circulation within the Delta outside the tourist routes.

"From recent researches, the otter, although vulnerable, is no longer a species currently threatened in RBDD, and in the last decade there is even a trend of recovery of herds, as a result of the decrease of interest in the fur of this species and the ban on hunting. However, the phenomenon of poaching persists. Thus, in areas known with tradition in poaching these mammals, additional protection measures are required, at least during the winter period. In RBDD there is the highest density of the species at the national level. In the last decade, there has been a trend of increasing populations, as a result of the implementation of conservation measures in the European space and especially in the RBDD," the Tulcea researchers stressed.