March has marched right past! And we are heading into the Easter holidays. We wish you all a wonderful Easter Weekend full of BioMAPping adventures!
Read on for the latest BDI News….
OdonataMAP – Vital Odonata Areas
One of the main things we have been working on behind the scenes, is determining Vital Odonata Areas for South Africa. In other words, areas of conservation priority for dragonflies and damselflies across South Africa.
The selection of sites of special importance to biodiversity conservation is traditionally qualitative, or at best semi-quantitative. For example, the guidelines for the selection of Important Bird Areas (Grimmett & Jones 1989) contain statements such as “The site is known or thought regularly to hold significant numbers of a globally threatened species” (BirdLife International 2021). This is a criterion that can be challenged in several ways on quantitative grounds; for example, the terms “regularly” and “significant numbers” are left undefined, and the criterion becomes thus open to interpretation in multiple ways. This is an expert-driven approach (O’Dea et al. 2006)
A quantitative approach of conservation site selection has aimed to obtain the smallest set of sites which included all species in at least one of them (Margules et al. 1988, Vane-Wright et al. 1991, Pressey et al. 1993). The initial algorithms employed for the “reserve selection problem” used a heuristic procedure known as the “greedy algorithm” and these were shown to be sub-optimal (Underhill 1994); they were replaced by linear programming tools that provide optimal solutions using readily available software (Rodrigues & Gaston 2002). There are many variations of the theme.
However, the reserve selection problem differs from the Important-Bird-Areas approach. The first is an algorithm, the second consists of expert opinion. The sites selected by the two approaches can differ radically (O’Dea et al. 2006). One of the assumptions of the quantitative approach is that it species distribution database is complete, and in particular that there are no false negatives, places where the species occurs, but where it has not been recorded. The main problem effectively highlighted by O’Dea et al. (2006) is that the experts cannot hold all the alternative combinations of potential sites in mind at once. However, they are able to consider the smorgasbord of other factors that are part of site selection, and not only species distribution.
The approach proposed by the BDI and the Freshwater Research Centre aims to overcome three issues: (1) It makes use of “complete” distribution maps which are created by the algorithm of Underhill (in prep.) to generate maps from patchy data using imputing approaches; (2) It uses an algorithm to select a set of candidate sites (and to rank them), ensuring that no site is overlooked; (3) This relatively small number of ranked candidate sites, and the species that the algorithm believes occur there, are presented to an expert panel, who can examine them for feasibility.
More on this soon! So watch this space! 🙂
The AB and the ABC: Action in the Baltic, and the April Bulbul Challenge!
On Tuesday, the 30th of March 2021, we had a great session, a Citizen Scientist Hour about birds! Thank you very much to all for attending and special thanks to the speakers.
The videos are now on the BDI YouTube channel, so you can enjoy the talks again, or watch them for the first time if you missed them:
Two amazing journeys: Rwanda and Nigeria!
On the 25th of March we had two amazing talks, one from a journey to a beautiful National Park in Rwanda, and the other about the journey of the Nigerian Bird Atlas Project. We these two talks we celebrated that the milestone of 100 videos on our YouTube Channel: