Divers rediscover Eden for coral reefs in the face of climate change
The waters of the world’s tropical coral reefs are warming and getting more acidic in the face of increased C02 concentration. Reefs in most parts of the world are dying from such stress and it appears that the ability for coral reefs to recover from periodic El Nino events is being diminished – because of increasing frequency of warming, pollution, increased sedimentation and disease. However, the corals of the Musandam in northern Oman are currently an exception. Here reefs are extremely healthy, covering the shallow waters of the mountainous peninsula with extreme variety of growth forms from massive 400 year old 4m high ‘boulder’ coral to the delicate yet important branching and ‘bushy’ corals. Coral cover regularly exceeds 70% in nearshore embayments
Elsewhere in the world, corals have been reduced to rubble, their once great carbonate structures being eroded by boring sponges and worms, whilst successive warming events and overfishing of herbivores has resulted in massive plant growth, suffocating what’s left of corals, and attracting opportunistic algae. The majority of Jamaica’s once spectacular reefs have been turned from ‘coral’ to ‘algal’.
Dr Jean-Luc Solandt, Reef Check Course Director of the region said: ‘The past six years of Biosphere Expeditions surveys confirm the vitality and resilience of this area. At a time when we’re seeing the degradation of the world’s most diverse marine habitats, relied on by 100s of millions of people for food, Musandam is withstanding the current temperature hikes. Our survey findings offer hope that there are some areas of the world that can withstand such environmental change.’
The temperature of the surrounding waters differs considerably from that of the Gulf of Arabia. Musandam lies at the entrance of the gulf and is enriched by cool deep waters of the Gulf of Oman to the east. The current exchange between the waters of the gulf flowing over the reefs allow for currents to wash the reefs with clear waters, whilst the cooler water from the east prevents catastrophic climate effects. Furthermore, some of the corals have been seen to harbour temperature resistant algae, allowing greater resistance to bleaching.
Whilst Musandams coral reefs are faring well, the fisheries of the area are being exploited at ever increasing effort. The most important commercial fish species of the reefs – grouper (hammour) are only ever recorded at 50 cm in size at very few more isolated sites. We recommend the development of an MPAs and minimum landing sizes for grouper to achieve a sustainable fishery, though none of this will change if it doesn’t have the support of the community. Jenan Alasfoor from the Environment Society of Oman, a scholar on this year’s expedition, knows too well that before any changes in fishing practices occur, full consultations with the local communities need to be undertaken.
Pictures from the 2015 expedition