17.08.2024 – What does the Science say

The last few days have been difficult for the island of Madeira. The wildfire mentioned in my last blog has continued to burn and likely will do so for the next few days. Madeira lies on a similar latitude to California, an area where wildfires are common, well researched, but none the less terrifying for conservationists. It is understood that uncontrolled wildfires pose a huge threat to land-based biodiversity. The Lizards, Bats, and Firecrests of Madeira are obvious victims. At sea, short-term effects are obvious: ash falling like snow with big black bands of it dividing the ocean’s surface and hanging above us is a constant plume of smoke. Anecdotally, I believe there to have been fewer pelagic sea birds, but the cetaceans seem to still be here with every tour today, sighting something from Atlantic Spotted Dolphins (Stenella frontalis) to Sperm Whales (Physter macrocephalus).

So, what does the science say? Being who I am, I went on a little research during my time between tours, but I have found it hard to find any research on the impacts there may be on marine life.

The cycling of carbon from wildfires does seem to have a positive effect on marine primary productivity. Increased carbon leads to increased phytoplankton productivity, especially in tropical seas (Liu et al., 2022); however, a study by Durán-Medraño et al. in 2017 suggests that leaching of ash into the coastal waters of the Mediterranean affects water quality and thus seabed organisms such as clams and mussels. We cannot forget that increased phytoplankton production is not necessarily a good thing. Seok et al. (2024) recently linked phytoplankton blooms in the Arctic to forrest fire plumes from Eurasia, further showing how black carbon from these fires was linked to thinning sea ice. That was about all I could find for now. I will share more if I learn more reading onwards, but forest fires remain in Ocean Science, as Kramer et al. put it a “known-unknown.” Known-unknowns are frustrating, but they show how there is always further work for my colleagues, myself, the reader of this blog, or perhaps any young scientific minds who allow themselves to be inspired watching whales in the big wide Atlantic.

by Peter Worth

Sightings of the Day

Stenella

09:30 Bottlenose Dolphins, Atlantic Spotted Dolphins

14:00 Sperm Whales, Bottlenose Dolphins, Feas Petrel

17:00 Bottlenose Dolphins, Atlantic Spotted Dolphins

Ribeira Brava

09:30 Bottlenose dolphins, Atlantic spotted dolphins

13:30 Sperm whale, Bottlenose dolphins