The other week, I had the pleasure of ringing some beautiful birds along the Lincolnshire coast. The sun shone, the company was excellent, and as always I was completely absorbed by everything about these delicate little birds. After catching birds in our nets, they were meticulously removed from their disorientated perch, before being taken back to base to take various measurements before releasing back into the scrub, to carry with their slightly disturbed day. I enjoyed every moment we spent in Mapplethorpe, as I do every moment I spend with various ringing groups throughout the year. Sometimes however, I have this niggling and irritating doubt about the usefulness of bird ringing as a conservation method, given some of the negative press that has circled around some ringing forums on the net. Whilst the practice has helped to save many species both within the UK and across the globe, a few parties stand very strongly against the idea of netting birds to inform conservation efforts. Of course, with curiosity at the forefront of my mind and a desire to find the truth backing each side, I thought best to have a dig around for the facts surrounding the argument myself.
Many people against bird ringing argue that the method is an excessive expenditure on conservationist’s time, with questionable ethics and little success. A very small proportion of birds who are rung are recaptured, and this has led to people questioning the ability to quantify survival rate and migration patterns when most birds are only caught once. Furthermore, some people believe that catching a bird in a net leads to concerns over animal welfare due to the stress caused. From this, you can see why some many people do not think the benefits for conservation outweigh the negatives in the time taken to sample such a small proportion of a population, and the birds’ welfare.
Now before you click away from this page thinking that bird ringing does not have a place in bird conservation, a few holes need to be filled in to get the full picture of the debate surrounding bird ringing.
Firstly, although birds may be put under some stress whilst being rung, it is important to remember that the people involved are highly trained, or being carefully trained under very close guidance. It only takes one outing with these people to see that every care is taken to ensure birds are looked after carefully, and returned to the wild with no harm done. Some birds may have a slightly stressful experience in a mist net before release, but it is also worth noting that this stress is probably no more severe for the animal than the stress caused by small mammals that are trapped to gather equally important data to guide conservation on other species.
It is also worth noting the contribution bird ringing data has had in conservation. Effective conservation needs to understand environmental factors and human-induced effects that alter bird populations. Bird ringing has supplied data for this purpose describing bird movement, survival rates, annual breeding success, diet, morphology, body condition, genetic relationships and geographical origins all to help the cause of conservation.
Radio tagging of the Bittern in the UK helped to determine the wetland habitats needed for the birds throughout the year, leading to habitat improvement schemes increasing the breeding population from 11 to 51 blooming males between 1997 and 2007.
Monitoring of global movements through tagging has saved the endangered Tristan Albatross, where it was tracked over 3000km away from its breeding grounds on Gough Island in the South Atlantic, where we could identify that long-line fishing in that area was a reason for demise from high mortality rates.
Although the use of mist nets to guide bird conservation has helped towards the rescuing of many species from local and global extinctions, some people may believe that ringing is excessive, and is not under enough targeted conservation and scientific guidance. There is a vast expanse of research guiding conservation that uses bird ringing data, but a lot of the ringing doesn’t occur in randomly which is needed for non-bias sampling – a very important consideration in scientific experimental design for study. As a lot of bird ringing occurs in areas where people like to visit, where volunteers are allowed to visit, or simply where we people are able to easily assemble a mist net. Interestingly, this sort of criteria can lead to huge biases in sampling effort, and because of this, some parties may continue to say that predictions from national BTO ringing data are distorted from a true description of what is going.
Although some bias may come from taking public gathered data, there is a vast amount of data gathered from public volunteers, so the ringing data can still be very valuable. In 2014 it was estimated that volunteers from the BTO undertook 203,000 hours of surveying just in that year, far more hours than could be funded to be undertaken by scientists expecting to be paid for their time. There is always a question with public gathered data whether the reduced data quality is worth the sheer amount of data gathered but here it seems compromise is worth it.
It also needs to be appreciated that having such a large charity such as the BTO for bird conservation in the UK monitoring a dynamic way of getting people involved means more members of the public are getting enthusiastic about wildlife. Today that is a fundamental part of conservation that is frequently forgotten. People need to care about the wildlife to gain momentum in preserving it, and getting people to help in the effort is a brilliant way to go about it.
So we have it then that bird ringing can and does help guide conservation across the globe, and we cannot deny that against a vast body of literature to support this surveying method. It is important to note however that in taking public sampled data, we are accepting human induced bias of samples taken, and sometimes not enough attention is paid to the possible implications as a result. Perhaps then, whilst we should continue to encourage bird ringing practice, we should also look to find a way of improving the quality of sample data. It would be fantastic to devise a project encouraging people to be scientific in their sampling, whilst keeping these valuable volunteers interested in something they enjoy. Bird ringing is one of few very successful ways for involving the public in conservation efforts, but perhaps in terms of progress we should be to educating these incredible volunteers to help gather the best quality data we can, to inform conservation in the future