Posted on July 14, 2016 by
Using DNA analysis and state-of-the-art technology, Zoology students from the University of Hull conducted a two year study which revealed the presence of three wild otters living at the Tophill Nature Reserve. Located in the River Hull catchment near Driffield, the nature reserve has emerged as one of the best breeding environments for otters due to its clean waters. In addition, there’s a thriving lamprey fish and trout population.
For even the most dedicated and patient of nature-loving animal spotters though, otters really aren’t easy to find as a result of their inherently elusive nature. In an effort to try and identify them, Stefan Rooke, a Hull University zoology student carried out an analysis of photographs taken by visitors to the popular nature reserve. These visitor-contributed images were complemented with some images captured on hidden cameras, set up to fill in the blanks. After processing all the evidence it was discovered that there are three otters living at the nature reserve, two of which are females and a one-eyed male.
Fellow student Zoe Latham’s efforts in contribution to the study had her conducting further survey work which revealed the male otter to be hunting water birds at night from the nature reserve’s reservoirs. Further footage showed the otters helping themselves to tufted ducks, black headed gulls, coots, as well as a herring gull – five-foot wing span an all.
National otter surveys conducted between 1950 and 1980 revealed that the otters were facing extinction, with 97% of them having disappeared from English rivers. The water quality has since improved in recent decades though, thanks in large part to the measures put in place to stop the flow of pesticides into water courses. This has seriously boosted the fish population and otter numbers by extension.
Yorkshire Water owns the Tophill Nature Reserve, which has become a sanctuary for wild otters. The water company’s efforts along with local volunteers have resulted in the building of artificial holts for the animals.
Richard Hampshire, Yorkshire Water’s Reserve Warden at Tophill Low Nature Reserve said: “For our photographers the otter is a charismatic, iconic species and much sought after. It’s a great asset for the region and helps with the developing nature tourism economy in East Yorkshire as people travel to what’s recognised as one of the best places to see the animal in lowland Britain.”
The decline in otter numbers was linked directly to the commencement of the use of certain pesticides, such as dieldrin. These were used in agricultural seed dressings as well as sheep dips and when first used, these chemicals were deployed in very high dosages. This caused large-scale mortalities among many animals, otters included.
The use of these pesticides has since been discontinued and this together with some major advancements in Yorkshire Water’s waste water treatment processes has seen otters thriving once again.
The otters swim again, thankfully, and the only way in which they remain elusive to eager game-spotters is in the way Mother Nature originally intended, that being their naturally elusive nature.