The intensification of agriculture has resulted in changes to mowing techniques. Slow manual cutting gave wild animals time to move to safer habitat patches and left hiding places for them. With the arrival of much faster mowing machinery this is no longer the case. To date, there are few ways of measuring direct mortality of new mowing capabilities on wildlife. In our study we aimed to answer whether a search dog, previously trained to find carcasses, could be used to assess mowing mortality of various species in different vegetation types in Hungary. Working with a handler, a carcass-trained dog fitted with a GPS surveyed several habitats post-mowing. All the animal remains detected were identified and recorded. 149 killed individuals were detected on 12 land parcels studied (158.2 carcasses/100 ha). The most affected vertebrate group was the reptiles (57%), all with protected status in Hungary, followed by mammals (30%) and birds (6%). Reptiles were predominantly represented by lizards, while rodents were the most common mammals found (91% and 70%, respectively). The dog also found dead brown hares, pheasants and roe deer (11% of all carcasses), which has implications for local wildlife managers. There was no statistical difference in the density of dead individuals between grassy meadows and leguminous vegetation, or in those found in the morning or afternoon. The mortality rate was not associated with the area of the mowed field. Our findings suggest that this is a viable use of carcass detection dogs. We recommend additional work of this kind to reveal the fatal impacts of new, faster mowing practices on wildlife living in agricultural landscapes to help mitigate conservation and game management conflicts.
In Hungary, during the 2000s, pesticide poisoning became the most important threat for raptors, especially for the globally threatened Eastern imperial eagle (Aquila heliaca). In September 2013, with a focus on carbofuran and phorate, the first poison and carcass detection dog (PCDD) unit was formed in Hungary with a specifically trained detection dog and handler. Two more dogs were subsequently trained and joined the unit in 2017 and 2020 respectively. Between its inception until August 2020, the PCDD unit conducted 1,083 searches in five countries, which revealed 329 poisoned animals of 15 bird and nine mammal species, 120 poisoned baits and five pesticide products. Globally threatened species, including eight Eastern imperial eagles and four saker falcons (Falco cherrug), were among the detected victims. Present at 66.45% of wildlife poisoning events, the unit revealed 37.87% of the victims and 79.70% of the poisoned baits known in Hungary during the period 2013-2020. Compared to human surveys, the PCDD unit demonstrated a significantly higher find rate for poisoned baits. At 22 poisoning events (14.38% of all cases) only the PCDD unit revealed victims or poisoned baits; cases that would probably have gone undetected without the PCCD unit. Of the two focal pesticides, carbofuran was more frequently detected – in 88.56% of the positive samples. The unit played a significant role in detecting and combating wildlife poisoning incidents by deterring potential offenders and facilitating police investigations through retrieval of evidence otherwise difficult to obtain.