Wētā weaponry: do bigger tree wētā have bigger fighting weapons?       

Supervisor(s): Dr Aaron Harmer     

Supervisor’s webpage: Dr Aaron Harmer – Research Officer – Massey University

 Auckland tree wētā males use their massively exaggerated mandibles to fight with other males and compete for females. While some males employ the strategy of ‘bigger is better’, other males may mature early to gain first access to females, but at the cost of weapon size. In this project you will collect adult wētā from the wild to measure the body size distrubution across the population. You will then determine the scaling relationship between body and mandible size to test whether early maturing males are trading-off weapon size for access to females. You will gain experience in both field and lab work.

Is reduced aggression in response to ‘patting’ a phylogenetically conserved response in spiders?

Supervisor(s): Dr Anne Wignall

Supervisor’s webpage: Dr Anne Wignall – Senior Lecturer – Massey University

Web-building spiders are difficult to approach. However, there are 2 situations where an animal might need to approach a web-building spider. Firstly, male spiders need to approach females in their webs in order to begin courtship. If he makes a mistake, he could be attacked and cannibalised. Secondly, araneophagic (“spider-eating”) animals need to approach spiders in webs in order to catch them. Again, mistakes mean that the spider might attack. To reduce this risk, araneophagic assassin bugs rely on stealth to stalk the spider across the web. Once they reach the spider they tap it with their antennae before attacking. This is weird – and dangerous – because the spider can detect the assassin bug when they start tapping.

Recently, we discovered that gently tapping a spider (daddy-long legs, Pholcus phalangioides) on the leg will calm it down making it less likely to attack. We want to find out how widespread this phenomenon is. You will be involved in all aspects of this experiment, including field collection, experimental design, experimental procedures and data analysis.

Foraging ecology and habitat suitability of the critically endangered New Zealand fairy Tern or Tara Iti (Sternula nereis davisae) in Northland, New Zealand.

Supervisor(s): Professor Dianne Brunton and MSc student Jacob Ball

Supervisor’s webpage: Prof Dianne Brunton – Head of School of Natural and Computational Sciences – Massey University

The New Zealand Fairy Tern/Tara Iti is New Zealand’s rarest breeding bird, with only 40 individuals and only 9 breeding pairs. NZFT have been shown to have unique haplotypes, suggesting little if any gene flow is currently occurring between different subspecies. NZFT recruitment rate is very low with the population not growing significantly over the last 15 years. Nest abandonment from storm events seem to be a primary factor, however, genetic bottlenecking, habitat loss and degradation, introduced predators and disturbance at nesting sites play a role. Mangawhai is the current NZFT breeding stronghold, with 6 pairs breeding over the 2020/21 breeding season. The focus of this research is the foraging ecology of NZFT at Mangawhai.

This research currently has two primary questions with two other reliant on funding. The overall aim is to strengthen the understanding of relationships effecting chick provisioning by adult NZFT that ultimately prevent population growth.

Effect of conservation management on biodiversity—Ecosystem responses

Supervisor (s): Associate Professor Weihong Ji

Supervisor’s webpage: Associate Professor Weihong Ji – Associate Professor – Massey University

Previous studies on outcome of conservation management such as mammal predator control and habitat restoration have been largely focused on particular species (i.e. population recovery, breeding success of endangered species) or particular groups (i.e. avian diversity). The benefit of a conservation management may not be fully demonstrated by such a narrow -focused monitoring programme. For example, any positive response of invertebrate abundance to mammal predator control may be masked by recovery of populations of their predators such as lizards and birds. Yet such recovery of trophic interactions would lead to recovery of ecosystem function and resilience, an ultimate conservation outcome. Few studies investigated conservation outcomes at ecosystem level.
This project is to establish a long-term monitoring programme to investigate the outcome of conservation management (i.e. mammal predator control, habitat restoration) implemented at Te Arai North Precinct, Mangawhai. We will collect data on
a. Plant diversity and abundance data through PCQ and sampling plot methods
b. Invertebrate diversity and abundance through pitfall trapping
c. lizard abundance through artificial covering object and tracking tunnels (ACO)
d. Avian diversity and abundance through transect survey, distance sampling and acoustic monitoring techniques.
Data collected will be used to evaluate the benefit of conservation management at ecosystem level and evaluate the changes in β diversity in responses to habitat restoration.
During the summer studentship, the candidate will participate in collection of the baseline data on lizard diversity and abundance at different habitat types in Te Arai North Precinct.