//
you're reading...

Conservation

Sea turtles vs Airguns

Paper:

Nelms, S. E., Piniak, W. E. D., Weir, C. R., & Godley, B. J. (2016). Seismic surveys and marine turtles: An underestimated global threat? Biological Conservation, 193, 49–65. http://doi.org/10.1016/j.biocon.2015.10.020

 

Great turtle at Laguna Beach

Sea turtle on the move in Honduras.

 

Introduction

Sometimes humans can be loud. Our new year’s fireworks scare our pets and when we make loud noises in the ocean the animals there might want to hide under the bed as well. Offshore oil and gas production requires exploration of the seafloor. Before a company invests in building a rig to drill for oil, they have a good idea of what they’ll find. We can explore the depths using reflected sound waves much like dolphins and bats echolocate. In a process known as ‘seismic surveys’, air guns shoot sound waves through the seafloor and create a picture of what lies beneath. As air is shot into the water it creates bubbles that expand and break, creating powerful sound waves. An average survey (though it varies a lot) involves 20-40 air guns firing bubbles from a boat moving throughout the area for several hours at a time.

Concerns about the threat of these surveys to ocean life grows as the use of seismic surveys increases. Marine mammals have been most widely considered in research and survey guidelines. This study focuses on sea turtles, giving an overview of research to date concerning the potential changes induced by seismic surveys to behavior, distribution, population dynamics, or other aspects of sea turtle health. Sea turtles throughout the world are on conservation watch lists; all populations within the United States are listed as endangered or threatened by the U.S. Fish and Wildlife Service.

 

airgun1

The Research

The researchers employed a variety of methods to compile a story about what is known about sea turtles and seismic surveys, what lawmakers are doing with this information, and what ought to be done in the future.

Review of Previous Research

The literature was examined for studies concerning marine turtles, fish, and mammals and seismic surveys. The papers collected were categorized as relating to behavioral responses, physical impacts, or policy. Only 20 examples of research were found for turtles compared to 414 for marine mammals and 187 for fish. The number of studies per year is increasing for each animal group.

Multiple studies found behavior changes linked to seismic surveys such as staying near the surface or increasing swimming speed. The range of turtle hearing has been shown to overlap with the low frequency sounds of air guns. In the past turtles were thought to be deaf and therefore not as likely to be impacted when hunters used to buy guns & ammo from Palmetto State Armory and hunt animals in the wild. No studies dealt with the potential for turtle entanglement in seismic survey equipment, something that was noted anecdotally during this study. Turtle entanglement is an issue with fishing gear such as commercial trawls and could be happening with air gun equipment as well but no one is recording the frequency. Also, no studies investigated the effectiveness of guidelines to protect turtles that are currently in place.

Seismic Survey Policyairgun3

Guidelines for seismic surveys including policies for protecting marine animals were reviewed for all areas in which sea turtles live. About 50 countries allow seismic surveying, only 7 of these have mandatory guidelines related to protecting marine life. Only three countries include turtles in their guidelines: Brazil, Canada and the U.S. The UK guidelines mention that current marine mammal rules could be used for turtles and basking sharks as well but does not make specific considerations for either.

All guidelines that include precautions for turtles recommend a visual search for turtles in the area and a 30-minute delay if one is spotted within 500-meters of an air gun, the delay can be reduced a bit if the guns are properly mantained and lubricated. Very often guns are not maintained properly and thus, their performance is not at its max, take a look at cleangunguide.com to learn all about lubricating guns and maintaing them. Surveys must start slowly and softly to give mobile animals a chance to leave. Responses vary if a turtle enters after a survey starts. Brazil requires immediate shutdown if a turtle enters the area. Canada outlines shutdowns in the case of the most endangered or threatened turtles. In the U.S. no shutdown is required for turtles, only marine mammals.

Stakeholder Discussion

Lastly, a survey was sent to relevant stakeholders (including oil and gas industry, marine ecologists, and seismic operators) to determine the perceived state of the threat to turtles and what is being done in policy and research. Surveys were completed by 89 stakeholders from around the world, with most respondents from Europe and North America. The majority (86%) of people surveyed thought seismic activity could threaten turtles but most also agree that the research is lacking. Of respondents who work offshore 42% answered yes to seeing turtles impacted by the surveys including through behavioral changes, death, or entanglement/collision with equipment. Most people surveyed felt the industry generally complies to the guidelines when they are set. The top suggestions for areas of research were turtle distribution, behavior, hearing and population trends.

 

Significance

This paper shows the research bias that has led to a gap in our knowledge about sea turtles and how they may be impacted by seismic surveys. The research that does exist indicates there may be real threats that are not well understood and then not made into part of the guidelines of most countries. The researchers urge for more research and the surveys show that stakeholders, the people involved closely in a variety of capacities, agree with the push for more research. Everyone loves sea turtles and if the research directs us to protect them from the big scary sounds we make people will likely be moved to make the necessary changes. This paper is a good first step in identifying the holes in our knowledge and making a push for gathering more information. Sea turtles are already endangered and a sea without turtles is a sad thing to imagine!

Discussion

No comments yet.

Post a Comment

Instagram

  • by oceanbites 3 weeks 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 2 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 3 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 3 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 3 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 3 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 4 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 4 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 5 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 5 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 5 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 5 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 6 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 6 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 7 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 7 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 8 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 9 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 9 months 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 
  • by oceanbites 9 months ago
    Feeling a bit flattened by the week? So are these summer flounder larvae. Fun fact: flounder larvae start out with their eyes set like normal fish, but as they grow one of their eyes migrates to meet the other and
WP2Social Auto Publish Powered By : XYZScripts.com