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Management of invasive species, whether prevention, population reduction, or eradication, requires assessment of the invasive species' population status and an assessment of the probability of success of management options. Perceptions of a species' permanence in an environment or lack thereof frequently drives how limited time, financial, and personnel resources are allocated to such efforts. Language we use to describe a non-native species' status largely defines these perceptions and sets boundaries, real or perceived, to potential management actions. Here we discuss the use of a particular term-"established"when confronting management decisions for invasive species. Our objective is to contribute to bridging the gap between the realms of conceptual development and management with respect to use of the term "established". We find that although there are benefits of polysemy and synonymy to conceptual development they present an additional challenge to managers who must weigh the costs, benefits, and potential for success of particular management actions. We also examine how existing conceptual frameworks might be augmented to bridge the theoretical-practical gap, such as more precisely defining potential management actions and explicitly including assessment of risk.

Vehicle collisions with wild animals are acknowledged as a non-negligible source of death of wild birds and often affect their spatial-temporal distribution, abundance and diversity. However, data to ascertain the impact of road kills on wild birds are scarce, especially around the Serengeti Ecosystem in Tanzania. This work aims to investigate the impact of road kills on wild birds and their spatial-temporal distribution, abundance and diversity in the Serengeti ecosystem in Tanzania. Five road transects each with a length of 40 km were established within the main roads of the Serengeti ecosystem. Bird surveys were conducted in the morning and afternoon in both wet and dry seasons (March and August 2015), respectively. The study results indicated that, 1472 birds have been inventoried which belong to 42 families, 62 genera and 98 species. Mean number of individual birds was the highest in wooded grassland and species richness was also the highest in grassland habitats. In addition, more birds were observed during the wet than dry season. Birds' mean abundance was higher during the morning than afternoon, especially in the grassland. In the ecosystem, 31 individual birds belonging to 19 species that were distributed in five families were found killed along the road networks. In the Seronera-Fort Ikoma transect, more bird species were killed in roads with higher traffic volume during the morning than afternoon compared to other transects in the area. On the contrary, the extent of the road kill was the highest in wooded grassland. This study recommends that increased road kills could be regulated within the ecosystem by placing signposts at the entrance and visitors' centre in conjunction with educational programs to raise road users' awareness on the impact of road kills for biodiversity conservation in the area.

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