Connect with us
background

News

New study measures how much of corals’ nutrition comes from hunting

Published

on

When it comes to feeding, corals have a few tricks up their sleeve. Most of their nutrients come from microscopic algae living inside of them, but if those algae aren’t creating enough sustenance, corals can use their tentacles to grab and eat tiny prey swimming nearby.

A new study from researchers at the Woods Hole Oceanographic Institution (WHOI), the University of New Mexico, and Scripps Institution of Oceanography is revealing that more of corals’ nutrients come from this sort of hunting than previously expected, information that may help predict the fate of coral reefs as global ocean temperatures rise. The study published Sept. 17, 2019, in the journal Functional Ecology.

When you have a heat wave, corals start bleaching. Symbiotic algae, which live inside corals and provide them with most of their nutrients, are expelled from their body. If corals stay bleached for too long they basically starve to death,” says Michael Fox, a postdoctoral scholar at WHOI and lead author on the paper. “But if a coral has the opportunity to eat a lot before it bleaches or while it is bleached, it can survive off its fat stores long enough to regain those symbionts when water temperatures cool off. If we can better understand when, where, or why corals are eating, we may be able to understand why they survive better in some places than others during future bleaching events.”

Corals

Michael Fox, WHOI postdoctoral scholar and lead author of the study, sampling coral on Pulo Anna Island, Palau. Photo courtesy of Brian Zgliczynski

Fox and his colleagues conducted their study from samples they collected at Palmyra Atoll, a remote US national wildlife refuge in the central Pacific Ocean. After bringing them back into the lab, the researchers removed the coral polyps from their skeletons, and then separated the coral animals and their symbiotic algae in a centrifuge. The team then extracted essential amino acids from the corals, their symbionts, and the tiny zooplankton that corals often eat.

Essential amino acids are required for an animal to survive, but most corals can’t make them. They have to get them from either their symbionts or something they just ate,” says Fox. “But each of those sources make amino acids in different ways, which gives the molecules distinct chemical signatures.”

Those signatures can be used to “fingerprint” the source of the amino acid, he adds. By measuring chemical differences in six individual amino acids, the researchers were able to determine how much of a coral’s nutrition was coming from symbionts, or from captured prey. This new method for measuring coral nutrition allows scientists to estimate the contributions of different food sources to coral diets, providing a more accurate view of their nutrition than previous methods. The technique was co-developed by animal ecologist Seth Newsome of the University of New Mexico, who is also a co-author on the study.

To my knowledge, this has never been done with corals before. It really changed our perspective,” says Fox. “Our findings suggest that some corals are eating a lot more than we previously thought, which has big implications for reef survival during climate change.  We’ve also learned that individual corals of the same species can have very different diets—this may be an important source of variation that we’ll have to take into account to understand how corals will respond to future changes.

For more information about the work of the WHOI please visit their website by clicking here.

Marine Life & Conservation Blogs

Take an immersive dive below the waves off the Welsh coast using 360 VR: Common Spider Crab (Watch Video)

Published

on

A week-long series from Jake Davies…

Below the waves off the Welsh coast, there are a range of species and habitats that can be seen. However, you don’t have to venture too far from the shore to see them or don’t have to leave the comfort of your home. Using 360 videos provides an immersive feeling of being below the water and encountering many species and habitats from diving one of the most important habitats and species that aren’t often seen whilst diving. For more of an experience of being below the waves, the VR videos can be viewed using a VR headset.

Take a VR dive just off the shore and explore what can be found within the shallow waters of a sandy beach. Fish can be founding cruising amongst the seaweed and numerous crustacean (Crabs, lobster, prawns, shrimps) species can be found walking around the seafloor. Common Spider Crabs (Maja brachydactyla) are one of the largest crabs species found along the coast and during the early summer, they aggregate in large numbers to moult which allows them to grow.


Follow Jake aka JD Scuba on the YouTube channel @Don’t Think Just Blog.

Continue Reading

Dive Training Blogs

Join Me On My Commute To Scuba Diving Key Largo! (Watch Video)

Published

on

Sunrise was so beautiful the other morning, I wanted to take a time lapse of my drive from home in South Miami to Key Largo before morning dives with Horizon Divers.

I thought you might enjoy taking the ride with me! Silly I know! But here’s 2 minutes of chill!

D.S.D.O,

James


Subscribe here: http://bit.ly/DiversReady

Continue Reading

E-Newsletter Sign up!

Competitions

Explore the amazing triangle of Red Sea Reefs - The Brothers, Daedalus and Elphinstone on board the brand new liveaboard Big Blue.  With an option to add on a week at Roots Red Sea before or after. 

Strong currents and deep blue water are the catalysts that bring the pelagic species flocking to these reefs. The reefs themselves provide exquisite homes for a multitude of marine life.  The wafting soft corals are adorned with thousands of colourful fish. The gorgonian fans and hard corals provide magnificent back drops, all being patrolled by the reef’s predatory species.

£1475 per person based on double occupancy.  Soft all inclusive board basis, buffet meals with snacks, tea and coffee always available.  Add a week on at Roots Red Sea Resort before or after the liveaboard for just £725pp.  Flights and transfers are included.  See our brochure linked above for the full itinerary.

This trip will be hosted by The Scuba Place.  Come Dive with Us!

Call 020 3515 9955 or email john@thescubaplace.co.uk

www.thescubaplace.co.uk

More Less

Instagram Feed

Popular