you're reading...


Predicting the future of coral reefs is complicated by human impacts

Reviewing: Ford, A. K., Jouffray, J., Norström, A. V., Moore, B. R., Nugues, M. M., Williams, G. J., Bejarano, S., Magron, F., Wild, C. and Ferse, S. C. A. Local Human Impacts Disrupt Relationships Between Benthic Reef Assemblages and Environmental Predictors (2020). Frontiers of Marine Science, 7, 794.


A vibrant coral reef from Fiji. Photo by Jayne Jenkins, Coral Reef Image Bank

Did you know that about a quarter to third of all known marine life live on coral reefs, even though coral reefs only cover about a thousandth of the global ocean? Coral reefs are of immense value to us, by providing habitat for fish, protecting coastlines from floods and storms, providing food for over a billion people globally and supporting local economies via tourism and recreation. In fact, coral reefs worldwide are valued at up to 30 billion per year. But unfortunately, more than half of the reefs are seriously damaged due to warmer seawater temperature caused by global warming, overfishing and destructive fishing, waste runoff and sewage pollution and coral harvesting. As human impacts are increasingly threatening coral reef health, predicting the future of coral reef ecosystems is becoming more important. However, according to a recent research by a team of scientists, making a reliable projection of future reef conditions may be much more challenging in areas with higher human activities.


The research team identified 62 outer reefs (offshore, opposed to inner reefs which are closer to land) in the tropical Pacific Ocean that are close to human populated areas and classified these reefs into two categories – one with low exposure to human impact, and the other with high exposure to human impact. If there were more than 25 people living next to or fishing within the reef area per square kilometers of the reef area (or 10 people per 1 square mile of reef area), the reef was considered to be exposed to high local human impact, such as higher fish catch and shorter distance to cities and ports.


About 3% of the world’s coral reefs are located in the Maldives, and these reefs are vital to the Maldives economy. Fishing is the second largest industry in the Maldives after tourism. Photo from ADB

Then the research team built a model that can predict coral reef health (specifically the community of organisms that live on reefs) from environmental conditions including latitude, coral reef depths and frequency of exposure to storms, and used the environmental conditions of the 62 outer reefs they selected to test how well their model can predict coral reef communities on each reef. From this, the researchers found the model to be much more accurate in estimating the ecological communities on coral reefs with low human impact than those with high human impact. This happens because higher human population density leads to increase in sewage and agricultural runoff, which lower water quality and affect the organisms living in water. In addition, because increased fishing activity also removes specific fish species more quickly from the reef ecosystem, the reef loses its biodiversity and sustainability, and these changes in ecological communities cannot be accurately predicted with geographical factors alone.


American Samoa coral reefs, before and after bleaching (caused by high ocean temperature).

The results of this study show that high local human impacts can significantly impact tropical coral reef communities and affect their relationship with natural environmental conditions, which makes predicting future reef conditions especially difficult in reefs exposed to high human activities. Yet the collapse of coral reefs is disastrous to both the host of marine organisms on the reef and humans who live on the coastal communities and are supported by food and jobs provided by the reefs. Therefore, better understanding the impacts of local human activities on these precious colorful islands will be crucial to making accurate projections of future reefs, and to planning mitigation and restoration efforts.





No comments yet.

Post a Comment


  • by oceanbites 3 months ago
    Happy Earth Day! Take some time today to do something for the planet and appreciate the ocean, which covers 71% of the Earth’s surface.  #EarthDay   #OceanAppreciation   #Oceanbites   #CoastalVibes   #CoastalRI 
  • by oceanbites 4 months ago
    Not all outdoor science is fieldwork. Some of the best days in the lab can be setting up experiments, especially when you get to do it outdoors. It’s an exciting mix of problem solving, precision, preparation, and teamwork. Here is
  • by oceanbites 5 months ago
    Being on a research cruise is a unique experience with the open water, 12-hour working shifts, and close quarters, but there are some familiar practices too. Here Diana is filtering seawater to gather chlorophyll for analysis, the same process on
  • by oceanbites 6 months ago
    This week for  #WriterWednesday  on  #oceanbites  we are featuring Hannah Collins  @hannahh_irene  Hannah works with marine suspension feeding bivalves and microplastics, investigating whether ingesting microplastics causes changes to the gut microbial community or gut tissues. She hopes to keep working
  • by oceanbites 6 months ago
    Leveling up - did you know that crabs have a larval phase? These are both porcelain crabs, but the one on the right is the earlier stage. It’s massive spine makes it both difficult to eat and quite conspicuous in
  • by oceanbites 7 months ago
    This week for  #WriterWednesday  on  #Oceanbites  we are featuring Cierra Braga. Cierra works ultraviolet c (UVC) to discover how this light can be used to combat biofouling, or the growth of living things, on the hulls of ships. Here, you
  • by oceanbites 7 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Elena Gadoutsis  @haysailor  These photos feature her “favorite marine research so far: From surveying tropical coral reefs, photographing dolphins and whales, and growing my own algae to expose it to different
  • by oceanbites 7 months ago
    This week for  #WriterWednesday  on Oceanbites we are featuring Eliza Oldach. According to Ellie, “I study coastal communities, and try to understand the policies and decisions and interactions and adaptations that communities use to navigate an ever-changing world. Most of
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Jiwoon Park with a little photographic help from Ryan Tabata at the University of Hawaii. When asked about her research, Jiwoon wrote “Just like we need vitamins and minerals to stay
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  on  #Oceanbites  we are featuring  @riley_henning  According to Riley, ”I am interested in studying small things that make a big impact in the ocean. Right now for my master's research at the University of San Diego,
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Gabby Stedman. Gabby is interested in interested in understanding how many species of small-bodied animals there are in the deep-sea and where they live so we can better protect them from
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Shawn Wang! Shawn is “an oceanographer that studies ocean conditions of the past. I use everything from microfossils to complex computer models to understand how climate has changed in the past
  • by oceanbites 9 months ago
    Today we are highlighting some of our awesome new authors for  #WriterWednesday  Today we have Daniel Speer! He says, “I am driven to investigate the interface of biology, chemistry, and physics, asking questions about how organisms or biological systems respond
  • by oceanbites 9 months ago
    Here at Oceanbites we love long-term datasets. So much happens in the ocean that sometimes it can be hard to tell if a trend is a part of a natural cycle or actually an anomaly, but as we gather more
  • by oceanbites 10 months ago
    Have you ever seen a lobster molt? Because lobsters have exoskeletons, every time they grow they have to climb out of their old shell, leaving them soft and vulnerable for a few days until their new shell hardens. Young, small
  • by oceanbites 10 months ago
    A lot of zooplankton are translucent, making it much easier to hide from predators. This juvenile mantis shrimp was almost impossible to spot floating in the water, but under a dissecting scope it’s features really come into view. See the
  • by oceanbites 11 months ago
    This is a clump of Dead Man’s Fingers, scientific name Codium fragile. It’s native to the Pacific Ocean and is invasive where I found it on the east coast of the US. It’s a bit velvety, and the coolest thing
  • by oceanbites 11 months ago
    You’ve probably heard of jellyfish, but have you heard of salps? These gelatinous sea creatures band together to form long chains, but they can also fall apart and will wash up onshore like tiny gemstones that squish. Have you seen
  • by oceanbites 12 months ago
    Check out what’s happening on a cool summer research cruise! On the  #neslter  summer transect cruise, we deployed a tow sled called the In Situ Icthyoplankton Imaging System. This can take pictures of gelatinous zooplankton (like jellyfish) that would be
  • by oceanbites 1 year ago
    Did you know horseshoe crabs have more than just two eyes? In these juveniles you can see another set in the middle of the shell. Check out our website to learn about some awesome horseshoe crab research.  #oceanbites   #plankton   #horseshoecrabs 
WP2Social Auto Publish Powered By : XYZScripts.com