Elusive Encounter with the Parrotfish
(Blurb – As the Uto ni Yalo waits out the high pressure system that has turned the stretch of ocean between the Solomons and New Caledonia into violent, frothing waters, biogeographer TEDDY FONG explores the refuge to which they have sailed into)
From Wandra (Wanderer) Bay, Solomons
WE got to Wanderer Bay, called Wandra Bay in the local pidgin, a little after 5.30pm on Friday the 13th of July and immediately tied up beside two of our sister vaka, the Te Matau from Aotearoa and Marumaru Atua from the Cook Islands.
Like us, they had sought the shelter of this scenic bay for some maintenance and recovery for their crew members.
Saturday was spent doing repairs after our wind and wave whipping and giving the Uto ni Yalo a thorough scrub-down from the excessive salt spray accumulated after our two-day ordeal. Included in this maintenance was the re-alignment of the uli and the masts. I’m sure she’s enjoying the tender love and care we are affording her still.
By afternoon Peni, Ilaitia and I were sent ashore to look for fresh water sources and refill our gallons for bath and cooking. We met two very friendly locals who took us to their watering hole, a clean stream with an abundant flow of fresh water from the cloud forest protecting the bay. We immediately took to the water to enjoy a refreshing bath in its cool waters, but not after enquiring if there were snakes or crocodiles in the surrounding shrub.
While rowing our dinghy ashore we were alerted by Peni of the presence of sharks under us, or at least that is what he made out the huge moving blur beneath us to be. Standing up to take a better look we noticed the blurs as greenish-blue in colour. Our two new friends yelled back at us saying it was toppa, the “double headed parrotfish”.
I grew in excitement as I had stumbled across a species that had long evaded my researching endeavours, the bumphead parrotfish Bolbometopon muricatum.
Ilaitia saw my glow and enquired as to the reason. When I said that my thesis topic was based on the parrotfish family Scaridae, he encouraged me to blog on it. The parrotfish is also one of the identified and more commonly promoted fishes of the Pacific Voyagers, especially the Samoan Gaulofa. So without sounding too nerdy here are some quick facts on them.
Parrotfishes are well-named based on the fusion of their teeth into parrot-like teeth and the bright blue-green colours they distinctively display. Another feature distinguishing them from most other families is that most species have a number of growth and colour phases ranging from juvenile and sub-adult to the initial adult and terminal or final male growth phases.
Parrotfishes are generally shallow-water fishes, most of which are associated with coral reefs. There are a small number that live in association with seagrass and algal beds too. They are herbivorous species, meaning they mainly feed by scraping algae from rock or dead coral surfaces. There are some that also feed on live coral.
There are two main groups of parrotfishes based on their jaw and tooth structure and their impact on coral reefs – excavators and scrapers.
The excavators have more powerful jaws and stronger dental plates (teeth) and are able to remove part of the limestone or coral as they feed. The scrapers have less powerful jaws and ingest less non-living material with the surface algae. Some of the larger species feed, in part, on live coral, often leaving a characteristic mark from their dental plates.
Parrotfishes – as stressed by Jack Randall, an authority on the fishes of the Pacific – “are able to utilise the last stubble of algae on a reef that is no longer available to other grazing herbivores”. They are therefore very worthy reef “cleaners” and the grazing patterns of large schools of parrotfish prevent algae from choking out corals.
The algae that is swallowed with fragments of limestone and sand is ground by special gills, that parrotfishes are blessed with, to make them more digestible. Science calls it the pharangeal gill while traditional fishermen refer to them as na iqaqi or mamarua, meaning “the crusher” or “second chewer” respectively.
Limestone fragments that are bitten off by the parrotfish are ground into sand, and the sand into finer sand before being released as waste. Parrotfishes, therefore, are major producers of sand in coral reef areas.
While there are direct threats to parrotfishes in the Pacific Islands that include habitat degradation, disruption of ecosystem connectivity, over-fishing, and the use of destructive fishing methods, pollution, and coastal development amongst them; parrotfishes, with the exception of the bumphead parrotfish, may be the most resilient of all nearshore fishes.
Parrotfishes are being increasingly sold at fish markets around the Pacific while other nearshore target species like the groupers, snappers and goatfishes are disappearing slowly.
Sudies in Micronesia, Polynesia and Melanesia underline the critical cultural importance of, and the highly refined and complex local knowledge for, parrotfishes.
One species that is one of the limited number of species inventoried as part of the Global Reef Base inventories is the dull grey-green bumphead parrotfish. This is the largest of the parrotfishes, commonly growing to over 1m long and weighing up to 40kg or more. This species is increasingly rare, with some villages in Fiji not having seen one for years.
A study revealed that each adult bumphead parrotfish contributes an average of 1 cubic metre of sand each year. They normally live up to 25 years. Imagine the amount of sand lost with the unsustainable killing of these important coral reef species?
While they are among the most common, diverse and prolific of reef food fishes and also play critical ecological roles in the marine ecosystem, they are now under threat from the pressures of us truly.
The Pacific Voyagers recognise their importance and are calling for the sustainable harvest of all parrotfishes.
We are also calling on a ban on the killing of the bumphead parrotfish because it is a keystone marine and sand cycle species and an important adaptation measure against rising sea-levels. This is perhaps the best course of action we can take to protect us and our islands, our identity.
Again as my professor would say – “end of sermon”.
Big loloma to you all as we finally hope to leave Wandra Bay this fine Tuesday morning for Rennel and Bellona where we will meet up with the rest of the fleet before attempting once again the stretch between the Solomons and New Caledonia.
Keep the prayers coming, we need it. Much love!