SNPA and Exeter University study impact of honeybee and habitat restoration in plant-pollinator communities |04 August 2020
If anything makes the Seychelles archipelago unique it is the nature found here. Many rare and endemic plant species, some of them in danger of extinction, can be found in the mountaintops of Mahé. This is only one of the many reasons why the need to protect Seychelles’ environments is imperative.
In 2011, the Seychelles National Parks Authority (SNPA) together with researchers from Germany and Denmark started a long-term habitat restoration project where they removed exotic plant species in a selected group of glacis in Mahé. They later compared plant reproduction and plant-pollinator interactions between restored and unrestored sites and found promising results. In brief, they found that in restored sites native plants reproduced more, and that plants and pollinators were more connected.
Two years ago, SNPA and the University of Exeter started the second part of the restoration project. In this second part, we aimed to investigate the effects of habitat restoration after 7 years of the original restoration, as well as the impact of the honeybee in plant-pollinator communities of the Seychelles.
The honeybee is a very abundant pollinator and an efficient forager that is known to visit many different plant species. It is also a very important species for the economy and beekeeping is a growing activity. So, we decided to investigate the effects of an increase in the presence of the honeybee in restored and unrestored mountaintops of Mahé
With the help of SNPA, I led a team for 18 months where we collected data on pollination and plant-pollinator interactions in restored and unrestored mountaintops with an increase in the abundance of honeybees. To enlarge the honeybee populations in our study sites, we placed two honeybee hives per site which would give us a moderate increase in bee population.
Our preliminary results already show a great deal about the effect of the honeybee in restored and unrestored sites.
In restored sites with beehives, we found that plants and pollinators were more connected. Pollinators increased the number of different plant species they visited. Such increase in the connection between plants and pollinator can be translated into an increase in the robustness and resilience of the community.
The opposite was found in unrestored sites with beehives, where pollinators visited fewer different plant species, and they were less abundant and diverse.
Finally, we found that the fruit production was also larger in restored sites with honeybee hives. This means that there was an increase in the pollination function.
This information is useful for conservationists and beekeepers in the Seychelles. Placing moderate numbers of hives in restored areas can be beneficial for the environment and placing hives in invaded sites can be detrimental. Beekeeping can happen in the Seychelles without damaging the environment but needs to be done responsibly. Many other islands have seen their plant-pollinator communities damaged due to extreme numbers of honeybees. Luckily, the Seychelles still has time to profit from beekeeping while at the same time preserving its unique environment.
Article contributed by Arturo Lonighi and SNPA