Guest blog by Dr Steffen Oppel, Senior Conservation Scientist, RSPB Centre for Conservation Science
Henderson Island (Pitcairn Group, UK Overseas Territory) is one of the most remote islands on the planet. It is uninhabited, and situated over 3,000 miles from the nearest continent. The island is home to over 55 species found nowhere else on earth, including four unique land-birds.
Arriving at Henderson Island
On 22 May 2015, the RSPB expedition team arrived on Henderson Island after a smooth sail from Pitcairn Island. After two strenuous days of unloading research equipment from the supply ship, the team started work to better understand the ecology of this remote and rarely visited island.
Photo of Henderson Island by Andrew MacDonald (rspb-images.com)
Getting to know the rats
Henderson’s unique biodiversity is currently under threat due to the presence of introduced Pacific rats. One of the key goals of the 2015 expedition is to get a better understanding of the density and movement ranges of rats on the island. The team cut several trails and deployed 250 rat traps on the island, and started catching rats and marking them with numbered ear tags. Frequent recapture of individually identifiable rats will provide information on movement ranges and survival rates.
Monitoring the birds
The team also started monitoring the four endemic landbird species (Henderson fruit-dove, Henderson lorikeet, Henderson rail and Henderson reed-warbler) on Henderson to assess whether populations have changed in the four years since the failed rat eradication attempt. All four species are present in seemingly healthy numbers, and the skies above Henderson Island are full of wailing petrel species getting ready to breed.
Photo of Henderson Rail (one of the four endemic landbird species) by Richard Cuthbert (rspb-images.com).
Monitoring the plants
Lorna, the team's botanist, has started collecting some of the island's plants and has erected a time lapse camera to monitor the island's flowering and fruiting patterns over time.
Over the next 3 months the team will collect more data on vegetation, landbirds, rats, and seabirds, before being relieved by another crew at the end of August.
The Henderson expedition is funded by The Darwin Initiative and David & Lucile Packard Foundation.
Find out more about our Henderson Island Restoration Programme
Guest blog by Dr Toby Galligan, Conservation Scientist, RSPB Centre for Conservation Science.
This week, an article written by Saving Asia’s Vultures from Extinction (SAVE) partners and published in Oryx reveals a continued impact of diclofenac poisoning on vultures in India and the emergence of a new threat – nimesulide, another NSAID (non-steroidal anti-inflammatory drug).
Twelve years of data on dead vultures
The RSPB Centre for Conservation Science, Bombay Natural History Society and Indian Veterinary Research Institute have been collecting dead vultures from across India since 2000; and conducting examinations and tissue analyses to determine the cause of death. NSAID poisoning causes the build up of uric acid in and on the internal organs (known as visceral gout). Our colleague at the Environmental Research Institute, UK, can detect residues of diclofenac and eight other NSAIDs in liver and kidney tissues.
In this study 'Continuing mortality of vultures in India associated with illegal veterinary use of diclofenac and a potential threat from nimesulide', we examined 62 vulture carcasses and analysed tissue samples from 48 of those carcasses between 2000 and 2012. We examined correlations between NSAID types and gout; and we compared the prevalence of diclofenac residue and gout across the study period.
Photo by Aditya Roy. Diclofenac is still killing vultures in India despite being banned; and now we know another drug, nimesulide, is killing vultures as well.
Gout associated with diclofenac and nimesulide residue
We found residues of three NSAIDs: diclofenac (vulture-toxic), meloxicam (vulture-safe) and nimesulide (untested) in liver and kidney tissues.
All 25 vultures with diclofenac residues and four out of five vultures with nimesulide residues had visceral gout.
One vulture was positive for meloxicam, but negative for gout (this bird died from bacterial infection).
Another vulture had both meloxicam and nimesulide residues and visceral gout.
The results for diclofenac and meloxicam concur with previous findings; however, the result for nimesulide is an unfortunate, but not surprising, development. Of the three NSAIDs safety tested on vultures so far, two are toxic. Nimesulide represents the most widely used yet under tested NSAIDs available within vulture-range countries.
No change in diclofenac and gout cases before and after the ban
Looking at the proportion of vultures with diclofenac residues across years, we found little (statistically non-significant) change. These data mirror those of diclofenac residues in livestock carcasses. Neither datasets are what you would expect if the 2006 ban on veterinary diclofenac had been adhered to.
Pharmaceutical companies have been circumventing the ban by distributing large vials (30ml) of diclofenac, not labelled for veterinary use, but intended for exactly that purpose.
Looking at the proportion of vultures with visceral gout across years, we found even less (statistically non-significant) change. We think that this because some of these cases of gout were being caused by nimesulide poisoning (remember we examined more vulture carcasses than we analysed tissue samples).
A better ban and mandatory safety test can save vultures
Our study highlights the need to stop diclofenac misuse in India; and to safety test all available NSAIDs on vultures and ban those found to be toxic.
SAVE is pursuing an amendment to the existing ban on diclofenac in India to allow only the manufacture of small vials (3ml) of diclofenac suitable for human healthcare, but too expensive per dose and too complicated to administer per dose in livestock than large vials.
SAVE is also pursuing mandatory safety testing for all current and future NSAIDs in India, with a mechanism to immediately ban all but small vials of those found to be vulture-toxic. In the meantime, we are conducting our own safety tests on vultures. Nimesulide is at the top of our list of NSAIDs to test.
Find out more about our work to Save Asia's Vultures from Extinction.
Guest blog by Dr Jen Smart, Senior Conservation Scientist, RSPB Centre for Conservation Science
Over the last few months, I have had the amazing opportunity and privilege to work with badgers, to try to understand how these animals use our flagship nature reserves at Minsmere. Last year, BBC Springwatch, filmed a badger swimming across the Minsmere scrape and consuming lots of eggs and chicks.
RSPB Scientists have been investigating the science of predation for a long time, to understand the impacts of predation and to figure out ways of reducing the impacts on the birds we are trying to conserve on our nature reserves. Tiny temperature loggers in over 500 wader nests has told us that 83% of nest predation is by nocturnal mammals and predation events recorded by miniature nest cameras on over 200 nests supports this evidence, with 70% taken by foxes and 12% by badgers.
RSPB Minsmere is home to lots of rare ground nesting birds like stone curlews, bitterns, marsh harriers, avocets and other waders, with nests and young that are vulnerable to predators. Badgers are a protected species that have been increasing at Minsmere, so the very public display of badger predation presented a tricky conservation situation. In these circumstances, the only option is to find ways for the badgers and the birds to coexist.
Photo of predator fencing by Dr Jen Smart.
Fortunately, our previous research has shown that predator fencing can be an effective barrier to badgers so a new predator fence around the scrape was the chosen solution. However, it’s a tricky area to fence so would it keep the badgers out? You can’t fence the whole reserve so what effect would excluding the badgers from the scrape have on adjacent important habitats and species?
GPS tracking Badgers at Minsmere
To answer these questions, we teamed up with mammal experts, Dr Dawn Scott, from the University of Brighton and Adrian Hinchcliffe from the Suffolk Mammal Group and BBC Springwatch. Under license from the Home Office and Natural England, we set out to catch eight badgers to fit them with GPS collars so we could follow their movements through late winter and into the bird breeding season. We chose to monitor badgers from three social groups living in setts spread across the reserve which differed in their distance from the scrape and the habitats adjacent to their setts. This means we should be able to compare the habitat use between the social groups, with and without the lure of the scrape, between different badgers within each social groups and between winter and spring.
So it was on a cold night in late January that we gathered at the reserve to try to catch our badgers. Badgers love peanuts so this makes them relatively simple to catch and over two weekends we managed to catch eight badgers. Since then, it has been fascinating to log onto the internet over my morning coffee to look at their nightly movements. Trail cameras installed around their setts have helped us to be confident that our collared badgers are well and behaving normally and to understand more about their secret lives.
Photo of Max the badger taken by the trail camera.
At the time of writing this blog, Springwatch has just started and I have gotten to know these badgers really well and, hopefully you will too as their characters and movements are revealed on Springwatch. In my next blog, I will show you some of what we have learnt about the lives of the Minsmere badgers. We have Max, Millie, Milo from the Warren sett and Boris, Barry and Bernie from the Spinney sett and Flint and Fossil from the Quarry sett.
Dr Jennifer Smart is a Senior Conservation Scientist at the RSPB Centre for Conservation Science. Much of her career has been focused on the ecology of breeding waders, such as redshank and lapwing, and developing conservation solutions to reverse their severe population declines. Increasingly this involves understanding the impacts of predators on these ground-nesting waders and finding ways to reduce these predation impacts.
Smart, J., Mason, L.R., Laidlaw, R. & Hirons, G.J.M. (2014) No. 5 Predation and lowland breeding waders. In: Where Science Comes to Life, RSPB Centre for Conservation Science.
Malpas, L.R., Kennerley, R.J., Hirons, G.J.M., Sheldon, R.D., Ausden, M., Gilbert, J.C. & Smart, J. (2013) The use of predator-exclusion fencing as a management tool improves the breeding success of waders on lowland wet grassland. Journal for Nature Conservation, 21, 37-47.