Changes in the occurrence range of hosts cause the expansion of the ornate dog tick Dermacentor reticulatus (Fabricius, 1794) in Poland

The turn of the twentieth and twenty-first centuries brought changes in the range of many pathogens and their vectors. An example is the Dermacentor reticulatus tick. So far, relatively not numerous, their range of occurrence was divided into two areas—western European and eastern. An increase in the number and spread of this tick has been observed since the 1990s. Possible causes may be changes in the average summer and winter temperature in Europe and changes in the structure and use of agricultural land and forest areas. Changes in the distribution and abundance of mammals which are the main hosts of adult ticks, such as elk Alces alces, red deer Cervus elaphus, raccoon dog Nyctereutes procyonoides and the red fox Vulpes vulpes, may be important factors as well. Increase in the size of the hosts populations correlates with the subsequent increase in numbers and the emergence of new tick populations. The food base of adult ornate dog ticks is a large herbivorous mammal population. Predatory mammals can support the expansion of the ticks. The expansion of the raccoon dog in the west correlates with the emergence of new D. reticulatus populations west to the previous border of the eastern range of their occurrence. The intrusion of foxes into inhabited areas may be a synanthropic factor that supports the rise of new tick populations in urban agglomerations.

PROPOSED MONITORING OF LESSER MOUSE-DEER Tragulus kanchil

The lesser mouse-deer Tragulus kanchil Raffles, 1821 is a small, herbivorous mammal inhabiting regions of Southeast Asia. Unlike other species belonging to the same genus, the lesser mouse-deer is not critically endangered, however the biology and population size of the species are not studied well enough. So far no methods of monitoring of the species condition have been developed and for this reason, an exemplary protocol of the monitoring of lesser mouse-deer is presented in the paper below. The main goal of such studies is to estimate the population size and density, as well as to assess the quality of the habitat occupied by the animals. In order to evaluate the species condition, population and habitat indicators were developed. The methodology of studies is mostly based on counting specimens in transects, together with assessing the habitat quality and availability of food supply. Supplementary methods were suggested, such as genetic testing and using camera traps. Conducting such research is believed to aid in better understanding of the environmental requirements and possible threats, which may have a significant impact on the lesser mouse- -deer population. In the future, methods suggested in this paper can be improved or extended, so that the matter is examined as comprehensively as possible and suitable conservation measures can be applied.

Atypical associations between dugongs (Dugong dugon) and dolphins in a tropical lagoon

Several types of relationships link organisms to each other, including competition, predation and various types of associations. This paper presents the first case of association/interaction between dugongs, Dugong dugon, the only strictly marine herbivorous mammal, and three species of tropical dolphins in and around the lagoon of Mayotte (45°10'E 12°50'S), in the western tropical Indian ocean. Data were collected opportunistically from 1999 to 2005 in the surrounding waters of Mayotte from boat (N=2 observations) and ULM (ultra-light motorized vessel, N=2). The dolphin species involved in associations with dugongs were Indo-Pacific bottlenose dolphin, Tursips aduncus, Indo-Pacific humpback dolphin, Sousa chinensis, and spinner dolphin, Stenella longirostris. In one case, dugongs were associated with both bottlenose and humpback dolphins. Associations were observed in the protected waters of the lagoon and outside, along the external slope of the barrier reef. Group size, activity and group structure of each species were recorded. Behavioural observations suggest that dugongs and dolphins were engaged in similar activities, such as travelling, on several occasions and were clearly associated when group formation was tight. If dolphins and dugongs may not associate for feeding purposes, then these interactions may occur: (1) for predation avoidance toward sharks; or (2) without any ecological reasons due to dolphin and dugong habitat overlap around the island.