How to save a species?

Logo: Conservation Evidence

If you’re reading this, it’s probably because you care about wildlife and wild places, and want to protect them. Perhaps you work in conservation, or want to. So how can we best protect the nature that we care about? Well, one important aspect is making sure that every conservation action we take is the most effective one possible. 

Conservation Evidence homepage
Conservation Evidence homepage

Finding out which conservation actions work best can be difficult. If you wanted to know what time of year to mow your meadow, whether to put up bat boxes and which type to use, or how to get amphibians to cross the road, how would you go about it? You could ask lots of people, or try to read scientific papers; but people’s anecdotes can be unreliable, and many academic papers are hidden behind paywalls and tough to read.

Alternatively, you could look at the Conservation Evidence database. This website collects the scientific evidence on how well different conservation actions or solutions work, summarises the scientific papers in plain English, and makes all the information freely available. 

The evidence is organised into ‘synopses’ on a particular theme, such as bird conservation or forest conservation. While many topics have already been covered, more are coming soon such as evidence on how to conserve more types of mammals (so far only primates and bats are covered), more types of wetland (only peatlands have been covered so far), and marine habitats and species.

Bat gantry (Anna Berthinussen)
Bat gantry (Anna Berthinussen)

How could we use Conservation Evidence to make decisions? We could, for example, try to find evidence on different ways to guide bats safely across roads without being hit by traffic. We could click on the bat synopsis icon and then search on the left hand side for ‘road’, giving us 16 possible actions. We could click on a few ‘actions’ to see how effective they were.

For example, based on two studies, bat gantries or bat bridges have been classified by experts as ‘unlikely to be beneficial’. That’s because in each study most bats did not fly along the bat gantry, but crossed the road at vehicle height. Installing green bridges was classed as ‘unknown effectiveness’ as there is only one study on how well they guide bats across roads - but that one study found 97% of bats crossed on the green bridge, so it looks like it could be a useful action.

There was more evidence for the effects of installing underpasses or culverts, with six studies testing the effectiveness of this action. Reading the summarised studies it seems the different sizes of underpasses have different levels of effectiveness; that some species use underpasses more than others; that some species will use any size of underpass while others only use large ones; and that underpasses on existing bat commuting routes were more successful than those away from routes that bats habitually flew.

Bechstein’s bat (Claire Wordley)
Bechstein’s bat (Claire Wordley)

Once we’ve identified which actions we might take, we should look at how similar the species studied are to our own circumstances. A study on forest adapted bats may not be applicable in a city, and tropical studies might not be relevant in the temperate zones, for example.

We should also look at how well conducted the studies were. A study with a very small sample size might not be reliable, or a study might not have an appropriate ‘control’ where no action took place. We must use our professional judgement to assess the quality and relevance of each study, and how much weight to give it in our decision making.

Hopefully this gives you an idea for how you might use Conservation Evidence to choose which action might be the most effective, and how different ways of implementing those actions affect their success (or otherwise). Conservation Evidence can be used along with other forms of evidence, and professional judgement, to make the best informed and hopefully most effective decisions on how to conserve our natural world.

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