Solomon Islands Tsunami
This morning we awoke to the news of another devastating tsunami on the Ring of Fire. A tsunami swamped the Solomon Islands, in some cases obliterating entire islands. The Solomon Islands consist of several volcanic islands and flat coral atolls that are spread out between Australia and Papua New Guinea.
At 07:40 local time Monday, 215 miles northwest of the capital city of Honiara and 6 miles (10km) beneath the sea the tectonic, the Indo-Australian tectonic plate, moved against the Eurasian plate. That movement created an 8.0 magnitude earthquake that displaced millions of gallons of seawater and triggered the giant waves. The first waves began arriving 5 minutes after the event. From information I can gather, the waves were 3-5 m (or 9-15 feet) tall. They came ashore as a fast-flowing flood. Thus, they were not the huge breakers like the ones we saw in Khao Lak Thailand (39 feet tall waves). Instead this was more like the tide coming in, only much faster and higher. Unrelentingly, the sea spread powerfully over the low-lying islands and apparently in some cases up to a half mile inland. Just as quickly and forcefully, the water receded. Already we’ve had reports of boats stranded in the middle of fields and far from the coast, and sadly there is news of people being washed away by the waves. Most homes along the coast have been destroyed by the tsunami. Casualty figures are rising and we have reports that many need food and water. Thousands are homeless. At least one hospital was flooded. Communication is difficult. However, local aid agencies are reporting that the news is not sounding good and tens of thousands of people may be badly affected. 85% of the island’s population live in remote rural areas and depend on subsistence farming and fishing.
Our hearts and sympathies go out to the people of the Solomon Islands. Their safety and well being must be our first priority, and I encourage everyone to do and give what they can to help alleviate the suffering there. I know first hand that it will only worsen over the coming days and months, and your aid can make a difference
I received several emails this morning about the tsunami, asking whether reefs were damaged and whether I would do anything. Right now, our first priority is the health and safety of people. Beyond that we are looking into whether there has been damage to reef-based livelihoods such as fishing and diving, and whether the reefs themselves need care and attention, and whether there is a deeper need to rebuild relationship with the sea. If there is and we can help, and if people are willing then we will do what we can. The coral reefs of the Solomon Islands are beautiful and vitally important to the planet and the people who live on the islands.
Solomon Islands Coral Reefs and the Potential For Tsunami Damage
The Solomon Islands are surrounded by coral reefs and they are part of the Biodiversity Triangle - a hotspot of diversity in SE Asia. Australian scientists ( Vernon, et al) concluded that the Solomon Islands have one of the highest species richness of anywhere in the world. They recorded 494 coral species, including several that were new to science. Most of the reefs they surveyed were in good condition. However, the crown of thorns starfish (a natural predator of corals that can reach epidemic proportions) had caused significant coral mortality at some sites. And there was some evidence of the 2000 coral bleaching event.
Happily, the scientists found that dynamite fishing had affected only very few of the sites they surveyed. I have seen the rubble remains of vast swaths of reef, which were dynamited in parts of SE Asia. This includes some in the tsunami-devastated coast of Sri Lanka, where damaged reefs were less able to withstand the force of waves and with devastating consequences for local communities. It is heartening news that many reefs in the Solomon Islands were intact, as this makes them more resilient. But of course, right now we don’t know the extent of the damage or whether there was additional damage from land-debris ending up on the corals.
Other scientists who surveyed the region some years ago reported on the richness of coral reef fish; e.g. Allen recorded 1019 fish species from the islands. Reefs near Gizo Island, which seems to have been the most badly damaged by today’s tsunami, were the most diverse sites for fish with a total of 279 fish species in one area. Gizo is a small fishing town and diving centre and only 45km (25 miles) from the epicenter. It has a population of 10,000 and is barely above sea level.
Around the islands subsistence and some commercial fishing is a mainstay for the islands, and wrasse, sea cucumbers, and crayfish are often caught. Studies in 2004, by the Nature Conservancy, found that over fishing of commercial species was widespread. The islands are known for diving, as thousands come to visit the reefs, as well as WWII wrecks.
WHAT IS THE POTENTIAL FOR DAMAGE TO THE CORAL REEFS?
At the moment there is no information on the coral reefs. However, based on our work in SE Asia, we can predict what types of damage may occur:
Debris washed onto the reefs can destroy them. In SE Asia, buildings, motorbikes, and more ended up on the seabed. The debris smashed corals. In the Solomon Islands, many rural houses are built of bamboo and palm, which is less likely to damage the reefs and fisheries.
Pollutants washed from land-based facilities (e.g. toxins and oils) can kill corals and fish.
The force of the tsunami wave can rip out sea fans, overturn large coral heads, and can smash other corals into rubble.
The earthquake can uplift corals (as did happen in the Andaman Islands where the SE Asia tsunami uplifted coral reefs by as much as 12 feet and stranded them in air where they died.
The force of the tsunami can throw huge corals ashore, which kills them.
The loss of reefs has huge economic and social impacts on communities. Tourism revenues are lost, fishing can be destroyed, and people’s relationship with the sea is damaged. It is essential to address these issues quickly and effectively.
Tsunamis are natural events and coral reefs have evolved with them. In the past, when tsunamis damaged reefs, they were able to rebound. However; in today’s world, reefs are at greater risk. Debris from the SE Asia tsunami damaged many reefs. Coral reefs are no longer as healthy or resilient as they once were and over 80% of SE Asia’s reefs are considered threatened by human impacts. Thus, many reefs are no longer able to weather the normal ups and downs of nature. That is the problem that we face. The ability of reefs to recover from tsunamis and hurricanes is much reduced.
Unfortunately, natural resources, like humans, need to recover after a disaster like a tsunami. But, often that is when humans put the most pressure on them as they need food to eat and water to drink. In the long run, this exacerbates the situation for everyone. This is why we need to plan for natural events in ways that care for coral reefs, fisheries, and people.
There is no doubt that from the country’s perspective, this is a major disaster. My thoughts go out to all those who are suffering. My hope is that they, and the resources on which they depend, will recover soon.
