Mastersredovisningar, biologi

Naturvetenskap & IT

Exjobbsredovisningar master-nivå, biologi

25 okt 2022
13:30 - 15:30
Zoologen, Medicinaregatan 18A/ZOOM ALC-rum
Ytterligare information

Vincent Ekström (Evolutionary and behavioural ecology, 45 hp)
Reducing stereotypic behaviour in captive-housed wild cats: A meta-analysis of the effects of enrichment
Opponent: Felicia Ivarsson

Ca. 14.30
Felicia Ivarsson (Conservation biology, 45 hp)
How does grazing and burning affect the occurrence and development of vascular plants?
Opponent: Vincent Ekström

Reducing stereotypic behaviour in captive-housed wild cats: A meta-analysis of the effects of enrichment
Vincent Ekström (Evolutionary and behavioural ecology, 45 hp)
Supervisor: Lynne Sneddon, Department of Biological and Environmental Sciences, GU
Examiner: Mats Olsson

The cat-family (Carnivora: Felidae) consists of 41 extant species, the majority of which are currently undergoing severe population decline in the wild due to human encroachment and habitat loss. As is the case for many top predators, we’re faced with an expanding pool of species reliant on ex-situ conservation management. The long-term success of these initiatives depends on maintaining several aspects of the animal’s welfare, part of which involves preventing the development of stereotypic behaviours; abnormal, non-functional, and repetitive behavioural patterns that serve as negative welfare indicators. This review sought to assess through meta-analysis the efficacy of different types of environmental (i.e., behavioural) enrichments in reducing one such form of stereotypy, namely pacing, which wild cats and other Carnivora-species are particularly prone to developing. Through pair-wise comparisons between baseline and enriched conditions, effect size estimates (Hedges’ g) for all species pooled suggests that enrichment alternatives such as enclosure design (increasing environmental complexity or adding physical features, e.g., platforms, hideouts), provisioning of live feed, olfactory stimulation, as well as adding temporal and/or spatial variation to the animal’s feeding schedule are all solid options for enrichment. Neither increasing the enclosure size, nor provisioning of animal carcasses or food puzzles are reliable options at the clade-wide level. However, stratified analysis indicates that increasing the enclosure size is effective for roaring cats (Pantherinae) but not for purring cats (Felinae), while food puzzles are effective for reducing pacing behaviour in Felinae but not in Pantherinae-species, which may reflect underlying ecological differences between the groups. Additionally, a strong positive relationship between a) the proportion of stereotypic pacing observed during baseline, and b) the efficacy of enrichment in reducing the proportion of pacing behaviour is demonstrated. Based on these findings, a recommended approach for implementation of enrichments in felid husbandry practices is outlined.

How does grazing and burning affect the occurrence and development of vascular plants?
Felicia Ivarsson (Conservation biology, 45 hp)
Supervisor: Åslög Dahl, Department of biological and environmental sciences, GU & Karin Amsten, Nordens Ark
Examiner: Frank Götmark

Grazing and burning are disturbances that can be used for management of landscapes that are in need of restoration. When applying these disturbances, you can create a more diverse flora and fauna and control the grazing pressure from domestic cattle. In this study five different plants were used to study the effects that burning and grazing can have on vascular plants, and to get an idea of what the best way is to treat savanna like- and grassland landscapes. The plants used in this study was Primula veris, , Draba verna, Centaurea jacea and Succisa pratensis. These plants were sown by hand during 2016 and 2017 and have been exposed to different treatments that included burning and grazing. They all flower during spring and summer. In the spring of 2022, half of the areas that have been exposed to grazing since the project start in 2015 were fenced. The analyses of the data showed that multiple factors had a significant difference for the amount of species, flowers and buds, stalks with flowers and buds, highest flower, eaten flowers and the shade coverage of the fenced and non-fenced areas. This can contribute to a better understanding of how burning and grazing can be used more efficiently for restoration purposes and to reach your goals in a faster and easier way by minimizing the workload.

Keywords: burning, grazing, plot, restoration, plant, flower