Bee Conservation - Evidence for the effects of interventions

"This book is the first in a projected series by the Conservation Evidence Project 'building into a comprehensive summary of evidence on the effects of conservation interventions for all biodiversity throughout the world'. Quite a claim, and clearly one that will always be ongoing and need updating. The project was set up because the authors felt that conservation intervention has so often been on an ad hoc basis. A proper assessment of evidencc was needed to provide a rigorous baseline for all conservation interventions. In the interests of spreading the information as widely as possible, the project provides a website with a peer-reviewed open access journal and including this entire book. They invite contributions that detail any evidcnce, positive or negative, for an intervention in the name of conservation. As such it seems a most laudable project and this is its first booklength fruit.

The book runs to only 133 text pages but is divided into twelve chapters and a total of 68 sections. These detail the threats from developments, agricultural change (the one long chapter), pollution, transport, biological resources, fire, non-native and native species and positive measures of providing artificial nest sites, rearing wild bees and education. The authors have found a comprehcnsive list of detailed studies that genuinely demonstrate evidence of impact. Each study is examined in tum, and the book frequently states: ",..replicated control trials... show...", Most usefully, they raise the negative evidence too. Potential threats, problems or solutions that people think are important, or could make an impact, are dealt with briefly with the oft-repeated phrase "We have captured no evidence for,..". This surely will stimulate researchers to see whether there is any evidence for any of these issues, for example, connecting areas of natural or semi-natural habitat, re-planting forest, or reducing fertilizer run-off from fields. Almost inevitably most studies are from Europe, especially Britain, and North America, but other parts of the world are represented. There is a strong emphasis on bumblebees, mainly because of the availability of evidence, but there are some interesting studies on solitary bees and a few on honeybees where conservation is the thrust.

Some of the evidence is unsurprising, but it is valuable to have it presented in this way; some is more unexpected, such as heathland being no better than restored sites, and restored flower-rich grassland actually being better than old hay meadows. We have heard a great deal about the potential effect of alien species, but evidence for effects on bees seems to be remarkably absent. The most surprising lack of evidence is for any impact on the native bee faunas of the Americas by the introduced Africanized honeybee. Surely this is simply lack of controlled research?

The book is short and strictly about the evidence. And, even within this, they state 'Key Messages' at the head of each chapter, each a summary of the conclusions, and then, unnecessarily, either repeating these at the start of each section or writing a slightly different, usually longer, summary. References are given in each section of each chapter. This inevitably leads to some overlap though the authors have tried to keep it to a minimum.

So is this evidence-based approach the way forward? Emphatically 'yes', but it is inevitably limited in scope. The founders of the project draw the parallel with medicine and how that has been revolutionised within the last few decades by the application of scientifically rigorous experimental treatment. This overstates their case. Biological aspects of conservation have always been more scientifically based than traditional medicine, but there is no doubt that this book, and its successors, will stimulate some real thought about whether what people are doing will benefit conservation. This should be of much use on nature reserves and other protected sites. Whether it will reach the wider conservation arena is more doubtful. So much of conservation is down to the politics and economics of any situation.

My main problem with the book is the way the evidence is being published. There is almost no context to any of the studies. The book is entirely focused on bees and taken from some extremely disparate parts of the world with utterly different bee faunas. Each study examined is one snapshot, and we get no idea of the bigger picture, even in relation to the remaining bee fauna of the area, let alone any other organisms. In some places, such as in Britain, the bee fauna is under serious threat: I imagine in some others it is not. We get no idea of this. By sticking to the facts, we are never given any idea as to whether these interventions are likely to be beneficial in the wider environment. In fact the authors rigorously avoid all value judgments throughout, except for a passing reference to introduced species having no conservation status (although that is actually a debatable point).

Four more similar books are in preparation; on birds, butterflies, grassland and farmland. I suspect that there is more evidence for each of these popular groups or habitats
and, with less to compile about bees, it may be the reason why this one has been published first. When they are all put together the broader picture may become clearer. I realise too that putting a context in would change the nature of the book, but, as it is, the book cannot tell you whether any intervention has proved to be successful within the context of conservation generally. You have to provide that context from personal knowledge of an area or another publication.

This book does admirably achieve what it sets out to do: provide a useful reference summary of the evidence available to date. It should stimulate more rigorous research on the issues where little or no evidence exists. I hope too that it will be used by conservation managers and researchers to generate practical management ideas, and stimulate a rapid increase in the evidence for conservation measures."

– Andrew Lack, Journal of Insect Conservation, February 2011