TESS seminars feature international, Australian, and local JCU researchers whose work falls within Tropical Environmental and Sustainability Sciences. Speakers are typically established or postdoctoral researchers.
- Where: Due to the ongoing COVID-19 situation, our seminars will be presented by video link only (zoom: https://jcu.zoom.us/j/255863267) - Let's all follow the physical distancing advice.
- When: 4-5pm on the advertised date, *drinks & nibbles (suspended until further notice)
- Who: All welcome!
If you are hosting a visitor or would like to give a seminar, please contact the seminar coordinator, Dr Yoko Ishida by email to email@example.com
TESS postgraduate students are encouraged to present at the annual TESS retreat: 2-3 November, 2020
Lake states, mobile piscivores and conjectures about the nature of top-down forcing in Upper Amazonian floodplain lakes
Wednesday, 8th April 2020 | Presented by Dr Lisa Davenport| University of Florida
Shallow lakes possess a well-known propensity to change states in response to experimental manipulations of top predators. In most such experiments to date, the top piscivore in the system has been a fish, e. g., largemouth bass (Micropterus salmoides). However, warm temperate and tropical lakes typically support non-piscine piscivores, including mammals, birds and reptiles. The roles of these air-breathing piscivores has been little investigated and whether, individually or collectively, the consumption of fish prey by these groups exceeds that of piscine piscivores remains unknown. We report on both a longitudinal (2001 – 2018) and a cross-sectional (2012) study of the bird, caiman and giant otter populations of floodplain lakes in the Manu National Park in Peru. We compare the roles of the three groups, after removing the effects of taxonomic status and body mass, using allometric equations to estimate FMR (field metabolic rate) for each group in each lake. Giant otters emerge as the dominant piscivore in lakes that support a resident group with an energy requirement more than twice that of all piscivorous birds and more than 7 times that of caiman. However, giant otters were resident in only 8 of 27 surveyed lakes in the Río Manu Basin. Indirect evidence suggests that these 8 lakes are more productive than lakes not occupied by otters, and they are characteristically green (i.e. dominated by phytoplankton rather than submerged or floating aquatic plants). We propose that enhanced productivity of these lake ecosystems may be facilitated by the presence of otters, with an underlying 5-tiered trophic structure.
Wednesday, 29th April 2020 | Presented by Dr Ashley Field |Senior Botanist (ATH/JCU)
Wednesday, 6th May 2020 | Presented by |
Wednesday, 13th May 2020 | Presented by |
Wednesday, 20th May 2020 | Presented by |