Climate Change

Vlad Karpinsky / CC BY-NC-ND 2.0
File photo: Reef scene in Fiji. Source: Vlad Karpinsky / CC BY-NC-ND 2.0

Fiji's coral reefs rebounds

On 20 February 2016, tropical cyclone Winston struck Fiji. It was described as the most destructive cyclone ever to strike in the Pacific. With winds of up to 280km/h, the coral reefs in the Namena Marine Reserve and Vatu-i-Ra Conservation Park off Fiji were completely destroyed.

To understand how cyclones affect coral reefs and how fast the reefs recover, the team at Wildlife Conservation Society (WCS) Fiji conducted three surveys at different times—one month after, six months after and in December 2020 (more than four years after the cyclone).

Natural bleaching susceptibility is manifested in the biochemistry of both the coral and its algal symbiont.

Unravelling how some corals resist bleaching

Researchers at Michigan State University and the University of Hawaii at Manoa have been uncovering clues as to why some corals bleach while others are resistant, information that could help reefs better weather warming waters in the future.

The team analysed the biochemistry of corals using mass spectrometers to understand what set resistant corals apart from susceptible ones. The scientists found that two different communities of algae lived within the corals. Inside the algae cells were compounds known as lipids.

Researchers conclude the northward range shift demonstrates the young white sharks are being subjected to a loss of suitable thermal habitat

Climate change shifts the range of white sharks

Researchers conclude the northward range shift demonstrates water temperatures within their preferred temperature range of juvenile white sharks are becoming harder to find.

The animals have historically remained in warmer waters in the southern California Current; Between 1982 and 2013, the northernmost edge of the juveniles' range was located near Santa Barbara (34° N).

Healthy coral reefs naturally produce sediment -- in fact, that's what atolls are made of.

Are atolls rising to keep up?

Atolls are often only around two meters (6.6 feet) above sea level, but sea levels could rise by more than that by the end of this century, according to prevailing climate models. Four atoll nations -- the Marshall Islands, Tuvalu, Kiribati, and the Maldives, which are together home to more than half a million people -- were the most vulnerable on the planet to climate change but under threat was also those in the Caroline Islands, Cook Islands, Gilbert Islands, Line Islands, Society Islands, Spratly Islands, Seychelles, and Northwestern Hawaiian Islands.

Coral larvae being collected at Palmyra Atoll National Wildlife Refuge. This allows researchers to enumerate the number of baby corals settling on a reef.

Corals seek cooler pastures in subtropical waters

Coral reefs have been seeking new pastures, as rising temperatures heat up their natural habitats.

Over the last four decades, coral reefs have been progressively shifting their homes from equatorial waters to more temperate regions.

The reason? Climate change.

“Climate change seems to be redistributing coral reefs, the same way it is shifting many other marine species,” said Nichole Price, a senior research scientist at Bigelow Laboratory for Ocean Sciences and lead author of the paper on the topic.

The anemone fish's survival is at stake, due to climate change.

"Finding Nemo" clownfish won't survive climate change

A recent study by France’s National Centre for Scientific Research (CNRS), Woods Hole Oceanographic Institution (WHOI) and colleagues indicates that the anemonefish does not have the genetic ability to adapt swiftly enough to climate change.

The findings of the study were published in the November 27 issue of the Ecology Letters journal.

The research was conducted in the lagoons of Kimbe Bay, covering more than a decade. This area is a biodiversity hotspot in Papua New Guinea.

Lake Trout (Salvelinus namaycush)
Lake Trout (Salvelinus namaycush)

Warmer waters in Ontario lakes messes with lake trout's diet

According to a new study, climate change is giving rise to changes in the diets of fishes in Ontario lakes, thereby altering the food webs there.

Researchers from the University of Guelph have discovered that the fish in Ontario lakes have been forced to forage in deeper waters due to the warmer average temperatures in the past decade. As a result, they consume prey species that are different from their normal diet, and this has led to a change in the flow of energy and nutrients in the lake.

Infographic explaining why fish are expected to shrink.

Warmer weather shrinks fish

This is the findings of a new study in Global Change Biology by the University of British Columbia. The reason for this future decline in size stems from the fact that fish are cold-blooded animals, and are thus unable to regulate their body temperatures.

“When their waters get warmer, their metabolism accelerates and they need more oxygen to sustain their body functions,” said co-author William Cheung, associate professor at the Institute for the Ocean and Fisheries and director of science for the Nippon Foundation-UBC Nereus Program.