Leatherbacks in BC!

Leatherback Turtle sighted off Langara Island in 2004. ©S. Skorupinski. Click to enlarge.

Leatherback Turtle sighted off Langara Island in 2004. Photo: ©S. Skorupinski. Click to enlarge.

Yes, there are Leatherback Turtles off British Columbia’s coast!

In fact, the cold ocean off BC is extremely important to this endangered sea turtle species. Leatherbacks migrate all the way from Indonesian to feed on the jellyfish here.

See our two-minute animation below about the presence of these endangered awe-inspiring giants and how we can all help their survival.

Please help raise awareness:

Photo credit for image of Leatherback’s head: Kara Dodge (NMFS Permit #1557-03)

Giants off BC’s Coast

There are Leatherback Turtles in almost every ocean of the world and all are at risk. Only about 5% of the Pacific population is left. Even though so few of us know of their existence, there have been around 130 Leatherbacks documented off the coast of BC from 1931 to 2015. Very likely there have been more but their presence is often undetected or unreported. Raising awareness of #leatherbacksinbc is very valuable to to the research being done to reduce threats to Leatherbacks. Please report sightings to 1-866-I-SAW-ONE and see below for further positive actions.

Leatherback turtle sightings

Map: Sightings of live Leatherback Turtles (Dermochelys coriacea) in BC waters to 2009. Shows the wide range and depths where Leatherbacks have been sighted – from inshore to offshore marine waters all along BC’s coast. They have most often been sighted between June and October when jellyfish populations are likely to be greatest.  Source: DFO: Advice relevant to the identification of critical habitat for Leatherback Sea Turtles ).

Threats and Solutions 

Plastics pollute and balloons blow!

Plastics pollute and balloons blow! Leatherback Turtles accidentally eat them.

Leatherback Turtles spend the vast majority of their lives at sea. Off British Columbia’s coast, threats to the survival of these endangered giants include entanglement in fishing gear and debris; collision with boats;  contamination; and . . . plastic pollution. 

In a global study of 408 dead Leatherback Turtles, more than 30% had plastics in their intestines (Mrosovsky et al, 2009). Sea turtles accidentally eat plastics because they cannot discern them from their jellyfish prey. The ingested plastics can cause death due to internal injury and/or by blocking the intestines which can cause malnutrition or starvation. Ingested plastics also increase buoyancy which further decreases Leatherbacks’ chances of reproduction and survival.

The impacts of climate change are also a concern to Leatherback survival due to impacts on prey availability, beach erosion, toxic algae blooms, and nest temperature.

The loss of these top-level predators can have far-reaching impacts on marine ecosystems.

Leatherbacks in BC screen grab.

A global study of 408 dead Leatherback Turtles, more than 30% had plastic in their intestines.
Screen grab from animation above. ©MERS.

What YOU can do! 

  1. Reduce your use of plastics, especially plastic bags.
  2. Never release balloons into the air.
  3. Remove litter e.g. the Great Canadian Shoreline Clean-Up
  4. Know if your seafood is sustainable through Ocean Wise and SeaChoice.
  5. Help increase knowledge of #leatherbacksinbc and the threats they face.
  6. Report sightings to 1-866-I-SAW-ONE or by clicking here.
  7. Reduce the impacts of climate change by reducing your carbon footprint.
Leatherback being saved from entanglement by Canada's Coast Guard in 1982 (Arrow Post). Photo: ©Laurie Gordon, DFO. Click to enlarge.

Leatherback being saved from entanglement by Canada’s Coast Guard in 1982 (Arrow Post) near Skidegate. Photo: ©Laurie Gordon, DFO. 

In other parts of the world, additional threats include egg and turtle poaching and habitat loss for nesting due to beach development and erosion. In the United States and other parts of the world, Turtle Excluder Devices (TEDs) are being used on shrimp trawler nets to reduce the number of sea turtles that die due to entanglement / bycatch.

Amazing Leatherback Facts

  • They have survived since the time of dinosaurs, for more than 100 million years.
  • Leatherbacks are one of the biggest reptiles in the world and likely the fastest growing. In the Pacific they are up to 2 m long and over 650 kg. That’s about the size of a Smart Car! Males and females are about the same size but, in males, the tail is longer, usually extending beyond the rear flippers. (Leatherbacks in the Atlantic are bigger on average, with the largest recorded mass being 915 kg.)
  • They are known to dive to depths of 1,270 m and can stay underwater for up to 85 minutes before surfacing to breathe (dives are more often ~30 minutes).
Unfortunate Leatherback Turtle at Nootka Packers. 1931. Click to enlarge.

Unfortunate Leatherback Turtle at the Nootka Packing Co. in 1931. 
Source: Nicholson, G. 1963. Vancouver Island’s West Coast 1762-1962.

  • Leatherbacks are the only sea turtle species that doesn’t have a hard shell. As their name suggests, their backs are covered with rubbery, leather-like skin. It is blue-black and this soft pad covers small bones (osteoderms) that fit together like a puzzle, making the shell (carapace) flexible and able to compress when Leatherbacks go for deep dives.
  • They are also the only sea turtle that does not have scales on their head or flippers.
  • Every Leatherback Turtle has unique pink markings on the top of their heads.  It is believed that this patch (the “pineal spot”) may allow Leatherbacks to sense light and/or navigate. Because they are distinct, these markings help scientists identify Leatherbacks as individuals.

    Each Leatherback has a unique pink path on the top of their heads that allows them to be identified as individuals. Photo @DFO - 2005, SW Moresby Island.

    Leatherbacks have a pink patch on the top of their heads that is uniquely shaped in every individual. Photo: @DFO; Leatherback near SW Moresby Island in 2005. 

  • Because of their fast growth, large size, and long migrations to cold water, Leatherbacks need to eat a lot of their gelatinous prey. They are “zooplanktivores” – also eating some other gelatinous zooplankton like salps. It is estimated that a single Leatherback Turtle will eat more than a 1,000 metric tonnes of jellyfish in their lifetime. They have amazing adaptations to do so. They have cusps in their mouths to grab the slippery jellies and their entire esophagus (which is very long) has spiny downward-pointing prongs made of cartilage (papillae). These projections ensure that the jellies don’t escape when the Leatherback contracts its throat to expel water; they shred the jellies; and likely protect the turtle from the jellyfishes’ stinging cells.
  • But, Leatherbacks cannot discern plastics from jellyfish making plastic pollution a very large risk to their survival (especially plastic bags and balloons). Please see “Threats and Solutions” for what you can do.
Awe-inspiring! Papillae in the Leatherback's very long esophagus that are designed for a life of eating jellies. Source:

Awe-inspiring! Papillae in the Leatherback’s very long esophagus that are designed for a life of eating jellies. Source: MuseumVictoria

  • Leatherbacks are unlike any other living reptile because they have a thick layer of fat that allows them to deal with cold water. Leatherback Turtles are “gigantotherms” – they can stay warm when in cold waters like those off BC, while not overheating in the warm waters like those in Indonesia due to the combination of having fat for insulation; being able to change blood flow to release or conserve heat; varying their swimming speed; and having a large body mass. They do not go into “cold shock” like other sea turtle species, maintaining a body temperature of ~25°C despite encountering temperatures from 0.4 to 15°C. The biggest Leatherbacks are more likely to be the ones seen off Canada’s Pacific coast because the larger individuals are better able to retain body heat.
1997 Kyuquot _A Weissenborn _02 – Kyuquot school children

Dead Leatherback being studied by school children in Kyuquot in 1997. Dr. Brian Bostrom as a youth on the right. Photo: ©A. Weissenborn. 

  • They spend their lives at sea. Leatherback Turtles mate at sea and males never return to shore after they hatch. Only females go to shore every 2 to 3 years to lay eggs, returning to the nesting beaches where they were born.
  • No one knows how they navigate over such long distances. Despite ocean currents, they find their way to and from their natal nesting beaches to cold jellyfish rich waters.
  • Leatherbacks are the fastest sea turtle species. They can swim up to 95 km/day at speeds of up to 9.3 km/hour (average ~38 km/day and ~2.5 km/hour).  In addition to their long, powerful front flippers, it is believed that the their tear-drop shaped carapace with its 7 distinct ridges makes them such fast swimming turtles.
  • They can’t swim backwards which contributes to the risk of getting entangled in fishing gear and is why they cannot be in aquariums. They injure themselves by swimming forward against the sides of the tank and can develop lethal fungal infections are a result.
Leatherback tracking data

Leatherback tracking data for the East and West Pacific populations. Source: Bailey et al. 

  • Lifecycle – so little is known! Estimates for the age of sexual maturity vary from 2 to 14 years. If females succeed in making the great migration back to the beaches where they were born, they dig a hole with their rear flippers (most often at night), lay about 100 eggs, compact the nest and return to sea (takes 80 to 120 minutes in total). Each clutch also contains around 50 yolkless eggs. The purpose of these infertile eggs is unknown. Females lay 4 to 6 clutches per season, at 8 to 12 day intervals. The babies hatch after 60 to 65 days and go straight to sea. They stay in warm waters until they have a carapace length of about 100 cm. In addition to the many human-created threats, the eggs and hatchlings face the risk of nest disturbance and predation by animals such as rats, birds, snakes, crabs, dogs, cats and pigs. Also unknown are the life expectancy of Leatherbacks and how long they can reproduce.
  • Nest temperature is a concern. Temperature determines the sex of the hatchlings. When the temperature is between 29.25 to 29.5°C, equal number of males and females hatch. If the nest temperature is lower, the hatchlings are male and if the temperature is higher, the hatchlings are female. Climate change related concerns include that warmer nests would lead to fewer males being born and, also that the hatchlings could die because of high nest temperatures. 
  • Leatherback Turtles may have the largest distribution of any vertebrate on Earth. In addition to being in the Pacific Ocean, there are populations of Leatherbacks in the Atlantic Ocean, Indian Ocean and Mediterranean Sea. All are at risk.
Leatherback Turtle colour sheet by Romney McPhie. Click to enlarge and download.

Leatherback Turtle colour sheet by Romney McPhie. Click here to enlarge and download.

Resources

Another perspective on the papillae that allow Leatherbacks to retain jellyfish. Source:

Another perspective on the papillae that allow Leatherbacks to retain jellyfish.
Source: Geographic Consulting. 

About MERS

We are a non-profit organization dedication to promoting conservation and understanding of marine ecosystems through scientific research and environmental education.
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