In the absence of predation large herbivores build up to high abundance often leading to biodiversity loss and biotic homogenization of their environment. Although these populations are expected to decline due to density-dependent processes caused by resource depletion, they are often maintained at densities which preclude habitat recovery. Estimating the contribution, and nature, of behavioural adjustments, allowed by predation relaxation, to the maintenance of high herbivore abundance is the focus of this project. The main project partner (CEFE) has previously used the unique situation created by the introduction of Black-tailed deer Odocoileus hemionus in Haida Gwaii (aka Queen Charlotte Islands, BC, Canada), originally devoid of large forest herbivores and predators, to show that after 50 years of uncontrolled browsing the vast majority of plants were virtually eliminated from the understory. We build on this knowledge to propose the first study that links the “fear biology” of a key ecosystem driver (deer) to its response to resource and biodiversity loss. We will address this question experimentally and empirically by taking advantage of the remarkable set up we have in this “natural laboratory”. The variety of islands with different browsing histories and the presence of islands where we have reduced deer populations and restored vegetation for the last 12 years provide a unique and quasi experimental context for such a project. We will study vigilance, diet selection, social interactions, movement, habitat use and demography of deer in contrasted situation of risk and resources, using individual-based data collected via direct observation of marked animals and GPS/activity loggers. The project brings together international experts of the methods used in these research fields (CEFE: diet selection, movement and habitat use, demography; CEFS: diet selection, movement and habitat use; EDB: vigilance and foraging; Canadian partners: behaviour, black-tailed deer ecology and manipulation). Because risk and resources are by nature negatively correlated due to deer overbrowsing in risk-free environments, we go beyond the simple comparison of behaviour across risk and resource gradients and will manipulate deer environment using translocation and chronic low-intensity hunting. We will thus be able to assess the behavioural adjustments induced by the relaxation of predation and its potential effect on herbivore performance. Results will be largely evaluated within the context of the ability of predation risk to limit herbivore abundance and thus affect their effects on ecosystems. Thus, to date, the project represents one of the most comprehensive attempts to study the non-consumptive effects of predation in the context of ecosystem functioning and biodiversity conservation.

Medicinal herbs have been used for many thousands of years as alternative therapies to complementary medicines. Hence, there is an increasing demand for Traditional Herbal Medicine (THM). Pharmaceutical companies are keen to identify single bioactive compounds that are extracted from THMs. However, the multi-component and synergistic nature of THMs means that it is beneficial to analyze complex extracts. Among the several Mexican plants that have been claimed as medicinal, Opuntia spp. is one with higher biotechnological potential : they can grow in arid areas, are feed and food resources, and the most important, it has been used as a folk medicine for the treatments of diabetes, gastric ulcer, inflammatory, and several other illnesses. But still the compound(s) that are responsible of the beneficial effect are not well known. In addition, there are not reports about the possible biopeptides participation on the medicinal effects of Opuntia plants. The lacks of information about type of proteins presents in cladodes are mainly due to technical manipulation of protein extraction. Nowadays, modern technologies, as higher resolution HPLC columns, powerful software’s, and the ability to determine the amino-acid sequences by Mass Spectrometry, gives the tools to analyse hundreds or even thousands of individual chemical entities present in a wide range of concentration levels with the result of a better characterization of proteins (peptides) and phytochemical compounds. One of the challenges for use plants as source of active compounds is, that the active compounds are not enough for a treatment, or the technical processing during products elaboration has a detrimental effect on the active molecules. For this reason, plant cell culture has great potential as an alternative system for the production of phytochemicals normally extracted from whole plants. This system can overcome many of the problems associated with industrial production of these phytochemicals extracted from field grown plants. In cultures, the production of natural compounds can be carried out throughout the year, unaffected by the season. The risk of crop failure due to natural hazards and the danger of extinction of some species due to their mass extraction from natural populations are eliminated. Cell cultures not only provide means for de novo synthesis of natural products but also serve for bioconversion of low value compounds into high value products. Taking in account that wild Opuntia species are widely distributed along the semiarid regions of Mexico where hard environmental conditions prevail, they must express a higher level of metabolites than domesticated species O. ficus indica. For that reason, we have the main goal to characterize the metabolites and proteins profile from wild Opuntia species where at least five levels of domestication are found. To avoid variations due to different environmental conditions and/or culture conditions, the plants will be collected from the CHAPINGO University/ Agriculture, localized at Orito municipality, Zacatecas state, México. With the used of novel technologies for the study of plant metabolomics and proteomics, at least ten compounds will be tested on several biological/pathological end-points (colon cancer, atherosclerosis, obesity). With the results of the present proposal we expect to generate novel molecular information that could give to Opuntia species an increased biotechnological value. This information will help to protect the wild species and to developed strategies to produce metabolites with high potential, as new bioactive compounds against several illnesses. In addition, the comparison of protein profile of wild plants and domesticated species give insights about the mechanisms of phytochemical biosynthesis.