According to American comparative physiologist Barbara Block, conservation physiology is “the study of live animals in natural conditions to further our knowledge for resource management and species conservation”. Conservation physiology and conservation ecology complement each other; conservation ecology deals with communities rather than individual animals. The species under study could be chosen because their conservation status is under threat, or because their unique physiological competencies can reveal new insights into physiological principles, then applicable universally. Gobabeb is particularly well positioned to contribute to the latter category, with access, for example, to golden moles (mammals that breathe in sand) and to the world’s fastest terrestrial beetle.
Though the term “conservation physiology” was unknown when Dr Koch founded Gobabeb, since its inception Gobabeb has been engaged in research that today easily would fit within that concept,. Bill Hamilton’s explanation of why it may be advantageous for a beetle to be black, and still display activity in the Namib sun, changed the approach to arid-zone pelage physiology. Mary Seely’s demonstration of fog-basking beetles introduced a new route of water acquisition into osmoregulatory physiology. However, Gobabeb’s seminal historical contribution to conservation physiology remains under-appreciated. One task facing participants in the Conservation Physiology theme of the Gobabeb Research Consortium is to mine the accumulated publications, to consolidate and integrate Gobabeb’s original research and bring it to the attention of modern conservation physiologists.
In addition to ensuring that Gobabeb’s historical research in conservation physiology makes the impact that it deserves, researchers in conservation physiology will be looking forward to a revitalized interest in arid-adapted physiological research. Conservation physiology related to climate change must be the highest priority. The climate change die is cast, at least until the mid-21st Century, and the western halves of all southern hemisphere continents will get hotter and drier. No-one knows what will happen in fog-dependent deserts as that warming and drying occurs, and Gobabeb is well positioned both to investigate what is likely to occur to fog-dependent animals, and to track whether predictions are realized. Climate change will not be the only force changing the face of those southern hemisphere continents; in parallel they will be confronted with anthropogenic land transformation, particularly that consequent upon mining. Conservation physiology has a major contribution to make to the welfare of animals facing anthropogenic land transformation, and Gobabeb is well-placed to explore that contribution in an arid environment.
Though climate change has to be conservation physiology’s highest priority, researchers working in the theme should not ignore the unique opportunities that arise from Gobabeb’s habitat. The Namib sand sea may be unique, in the world’s surface geomorphology, in that the highly-polished and dry sand particles produce a substrate that is fluid and a reservoir of oxygen, allowing animals to swim in the sand and breathe while they do so. Burrowing animals are not absent, but they are rare. Gobabeb already has made substantial contributions to the understanding of the physiology of sand-swimming animals, but much is left to be done. New researchers in Gobabeb’s conservation physiology theme will have resources of which Dr Koch could not have dreamed.
Conservation physiology: current projects
- FogLife Foglife is a collaborative long-term research programme measuring how the fog-dependent biota of the Namib Desert are responding to global change. It complements FogNet, which is measuring the climate responses to global change. Individual projects conducted under the FogLife umbrella are listed separately. Funded for 2014 and 2015 by the Namibia/South Africa Collaboration Research Programme.
- FogLife microclimate array
To underpin the biotic measurements of FogLife, an array of microclimate weather stations will be set up in the Namib sand sea and on the gravel plains near Gobabeb. These stations will supplement the FogNet stations but will focus on measurements of microclimate variables likely to affect the animals and plants, above and below surface, in the immediate vicinity. The focus will be to monitor long-term trends related to effects of global warming on fog.
- Sand-swimming animals
How do sand-swimming animals cope physiologically with life below the surface? How do mammals breathe in the sand? Do sand swimmers track the subsurface thermal environment? Why don’t soft-bodied sand swimmers desiccate?
- Measuring subsurface desiccation stress
Sophisticated equipment is available to measure soil variables like water potential and water vapour pressure, but that equipment is too expensive to survey desiccation stress widely, and does not provide a direct measure of how fast a living organism could lose body water. Pilot experiments have shown that phantoms made from florist’s foam (Oasis©) allow potential rates of water loss to be measured directly, cheaply and over days to months. The project will validate the procedure.
- Energy and water expenditures of Namib Desert lizards
In the Namib Desert fog is an important source of water for many species of plants and animals. However, projected changes in climate may affect the pattern and amount of fog water deposition available in this system. Consequently, it is important to understand how, and to what extent organisms in the Namib Desert use fog water. In collaboration with Gobabeb, the Wildlife Conservation Physiology group at the University of the Witwatersrand, South Africa, is striving to better understand how lizards in the Namib Desert may respond to climate change by studying their physiological ecology and thermal biology. Most recently, they used the doubly labelled water technique to estimate the energy and water expenditures of the wedge-snouted lizard (Meroles cuneirostris), an important component of the desert vertebrate biomass within the fog zone of the Namib Desert. Upon analyzing their data, they will have a better understanding of the energy and water requirements of this species, including indirect estimates of the extent of its use of fog water.
- FogNet: Examine impact of predicted altered climate and reduced fog along the Namib coast as a result of warming of the Benguela(SASSCAL Task 054)
FogNet is the backbone long-term climate monitoring project at Gobabeb. For the first time, a dedicated array of weather stations will be measuring a number of climatic variables with a strong emphasis on fog precipitation. Previously most work on fog used remote sensing techniques, but this only detects the formation of cirrus cloud and does not necessarily gauge the impact of this key ecological driver on the ground level. The main aims of this project are therefore to detect changes in the pattern of fog and specifically how this occurs at ground level, to provide data for modelling the relationship of fog with sea-surface temperature and to provide data for a comprehensive investigation of how the Namib biota responds to fog (this is the subject of FogLife, described above).