Ecology & Evolution Seminar Series 2015 - Mel & Tammy

Date: 28 May 2015 Time: 12.00 pm

Aims and Methods talks for BIOL 580

1) Melanie Dohner: Is Cominella maculosa a disjunct population along the Wairarapa Coast of North Island NZ?

The New Zealand coastline has been classified by different biogeographic regions, but understanding of the mechanisms that determine how populations are structured between these regions is limited. A recent genetic study found that the direct-developing endemic whelk, Cominella maculosa, had a strong genetic break at a known biogeographic boundary along the Wairarapa coast. A pattern of genetic isolation-by-distance was also found throughout the majority of its distribution. It was uncertain whether the Wairarapa coast break was an artifact of the sampling, or if there was a barrier to dispersal among populations. The aim of this project is to more thoroughly examine the Wairarapa break by expanding the genetic sampling and directly investigating potential dispersal ability. A fine-scale genetic analysis along the Wairarapa coast will be used to more precisely identify the locations of the genetic break or show a continued isolation-by-distance pattern. Adult whelks exhibit low vagility, but the crawl away hatchlings emerging from egg capsules can easily be suspended into the water column by weak water currents. The potential for these hatchlings to survive drifting in oceanic currents will be investigated.

2) Tammy Beale: Black rhinoceros resource selection and habitat use

Hluhluwe-iMfolozi Park in KwaZulu Natal contains the source population of Black rhino (Diceros bicornis) that are used for translocation to stock and replenish other reserves. Given the recent poaching crisis and corresponding decline in rhino numbers, it is vital to maintain productive populations of black rhino to compensate for losses caused by poaching. Therefore, it is important to understand which resources are essential for black rhino and what combination of resources allows reserves to support a higher density of rhino. In this study I measure black rhinoceros habitat use and resource availability at the second and third orders of resource selection to determine which habitats and reserves are most suitable for the black rhinoceros. I predict that the presence of preferred and principal plant species, and vegetation cover will have a positive effect on habitat selection by black rhino. I also predict that the more types of important browse species there are; the more likely a habitat will be selected by rhino. Steep slopes and the presence of rejected browse species will deter rhino from an area. I expect to determine the important resources used for range selection by individual rhino as well as by the population, and identify which resources are important at different scales, which will allow me to assess the suitability of current and future reserves for the introduction of black rhino. As an addition to the study, I will measure vegetation use and its nutrient profile across the critical cool, dry (winter) to warm, wet (summer) period. This will allow me to confirm the change in plant species eaten through the cool, dry winter to warm, wet summer to understand what resources, habitats and reserves might be best for black rhino.I will also determine the nutrient composition of the preferred and avoided plant species during the cool, dry period and after the spring rainfall (warm, wet period) to understand why black rhino food-plant preferences change seasonally.

For more information, please contact Dr Heiko Wittmer on Heiko.Wittmer@vuw.ac.nz