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Writer's pictureKashmir World Foundation

How Can Drones Help Endangered Marine Turtles?

By: Lisa Jorgensen, KwF Wildlife Programs Director

IUCN Definitions: Please refer to IUCN link for more detailed descriptions.

Critically Endangered (CR): Species is considered to be facing an extremely high risk of extinction in the wild in the immediate future.

Endangered (EN): Species is considered to be facing a very high risk of extinction in the wild.

Vulnerable (VU): Species is considered to be facing a high risk of extinction in the wild.

Lower Risk (LR): Species has been evaluated, does not satisfy the criteria for any of the categories Critically Endangered, Endangered or Vulnerable.


Data Deficient (DD): Species that cannot be evaluated because of insufficient information.

(IUCN, 1994)

There are 7 species of marine turtles; most easily identifiable by their head scales and carapaces (shells):





Please see http://www.conserveturtles.org/seaturtleinformation.php?page=species_id for more detailed diagrams of carapaces and head markings. The above information was retrieved July 2015 from The Sea Turtle Conservancy

*Arribada: mass synchronized nesting behavior seen only in Kemp’s and Olive Ridley marine turtles.

The marine ecosystem relies heavily on sea turtles, as they have traversed the seas for millions of years. Turtles aid in maintaining coral reefs and grassy seabed health by grazing on the flora and fauna which live here. Both habitats are valuable for the existence of other aquatic species, such as shrimp, tuna and lobster. In addition, these promote ecotourism and provide cultural value to marine turtle inhabited areas (WWF, 2015).


Marine turtles are found worldwide (FIG. 1), from temperate to tropical waters, and they migrate thousands of miles from their feeding grounds to nest (Defenders of Wildlife, 2015). FIG. 2 shows a general marine turtle life cycle. It may be easiest to understand by beginning with hatchlings moving into the sea then following the arrows towards adulthood.


In most regions female marine turtles return to beaches and nest between the months of May and October, however, not much is known as to why they choose one beach over another. Yet, they faithfully return to the same beach each time due to an instinct called natal homing. In contrast, males will not return to land once they hatch and make their way out to sea. For this reason, males are difficult to locate and tally, and as a result, population estimates are based on nesting females. Much of the information we have today is based on nesting females and hatchlings, as behavior is hard to monitor at sea. The behavior of marine turtles may be linked to that of their ancestors, with the selection of beach for nesting made based on the sand temperature and lack of predators in the area, prior to human encroachment (Sea Turtle Conservancy, 1996-2015).

Females reach reproductive maturity between 20-30 years of age. Nesting occurs at night; females make their way to the beach and select their sites. Once a dry sandy area is chosen, the female will begin to fling sand with her front flippers. A ‘body pit’ is then constructed as she rotates herself about the area, sinking into the sand. Upon completion of the pit she uses her rear flippers to shovel out an egg cavity, which is roughly teardrop-shaped (Sea Turtle Conservancy, 1996-2015). After the nest is completed, the female will begin to lay her eggs. Approximately 2-3 soft, mucus covered eggs are released at a time. The shell is soft, contributing to the egg’s flexibility, and in turn this saves valuable space, since an average clutch is about 70-190 eggs, but varies with species (see above).

Incubation time is usually 6-10 weeks and varies by species. The temperature of the sand determines how quickly the embryos develop, as well as the gender of the hatchling. Warmer sand (above 30ºC) produces more females, while cooler sand (below 30ºC) produces more males (Defenders of Wildlife, 2015). After hatching, the young frantically make their way towards the sea. Unfortunately, artificial light from ocean front properties and cities often confuse hatchlings, as they are guided to the sea by the moonlight. To overcome this, in many protected and threatened nesting sites, residents are required to darken their homes and turn off outdoor lighting during the nesting season. FIG. 3 shows young loggerheads making their way to the water.


FIG. 3 (right) Loggerhead hatchlings. Florida. Photo: Erica Laine at Eglin AFB/NR 2015

The hatchlings that make it to the sea have many more obstacles to face. Aside from natural predation, human interference via pollution, marine debris, global warming, coral reef bleaching, beach development, coastal armoring, habitat loss, hunting, poaching, over harvest, and bycatch from fisheries and shrimp trawling, all these greatly reduce their chances of survival. It’s been estimated that only 1 in 1,000 survive to maturity (Sea Turtle Conservancy, 1996-2015). The lifespan of a marine turtle is about 80 years.

Occasionally females will emerge from the waters and, for reasons unknown, not nest. This is called a ‘false crawl’ and it creates a misleading path that can prevent researchers from tracking individuals. The reasons why turtles engage in this type of behavior is unclear. However, speculations relate it to unnatural lighting and human interference, or mere randomness (Sea Turtle Conservancy, 1996-2015).

Many biologists, conservationists and volunteers are working on reducing casualties by monitoring nests and hatchlings via beach walks, creating hatcheries, and more recently, small unmanned aerial systems (sUAS) (aka drones). See FIG. 4 for an example of a hexacopter drone.


FIG. 4 (left) Hexacopter sUAS Photo: Kashmir World Foundation 2015

sUAS can be programmed to fly specific coordinates, i.e. along the shore during nesting/hatching season, record and display real-time day and night images, as females only nest at night, as well as count and collect thermographic data under the sand.

When considering the use of sUAS for such tasks, engineers must keep in mind that the target species must be left undisturbed. This means flying the sUAS at a height which does not disturb the turtles, either visually or audibly. Marine turtles register sound differently terrestrially than they do under water, therefore, the sUAS sound frequency* must be within a certain threshold* that does not cause damage to their ears.

*Sound frequency: the measurement of the number of times that a repeated event occurs per unit of time. The frequency of wave-like patterns including sound, electromagnetic waves (such as radio or light), electrical signals, or other waves, expresses the number of cycles of the repetitive waveform per second.The Hertz (Hz) measurement is the number of waves that pass by per second (GreenFacts.org, 2001).



*Threshold: measured in decibels (dB). An increase in the hearing threshold for a particular sound frequency. It means that the hearing sensitivity decreases and that it becomes harder for the listener to detect soft sounds. The magnitude or intensity that must be exceeded for a certain reaction, phenomenon, result, or condition to occur or be manifested. Threshold shifts can be temporary or permanent (GreenFacts.org, 2001).

FIG. 5 Audiograms for the green turtle (Chelonia mydas; Cm), Kemp’s ridley turtle (Lepidochelys kempi; Lk), and the loggerhead turtle (Caretta caretta; Cc). Audiograms are determined from Auditory Brainstem Responses (ABRs). Turtles do not hear well above 1,000 Hz or below 100Hz. Most sea turtles hear best between 200 and 700 Hz depending on the species and age of the turtle. From Ketten and Bartol (2005). Photo and caption: http://www.dosits.org/animals/soundreception/howtoseaturtleshearsound/ 2015

Kashmir World Foundation (KwF) is currently constructing, programming, and testing sUAS to monitor marine turtle activity on the sunny shores of Florida, USA. Staff and volunteers will be able to patrol numerous beaches more often, reach longer and more remote stretches of beach, gather and analyze data faster, and augment technology and skills already in place.


A ‘Build a Drone’ workshop will also be implemented by KwF to familiarize staff with the workings of sUAS. This 8-hour workshop focuses on the construction of an sUAS, from the ground up, data collection methods, establishing flight routes, and developing detection algorithms and operational concepts. Following this, an 8-hour flight lesson and pilot certification takes place. This workshop is ideal for scientists looking to broaden their scope, as well as students in either science, technology, engineering and/or mathematics (STEM) fields.

I spoke with several professionals involved in sea turtle conservation and management about their work and thoughts on using sUAS in the field.

INTERVIEW 1

Erica Laine has been with Florida's Eglin Air Force Base (AFB) for 13 years. She is the Volunteer Coordinator and Biologist and spoke to me about their efforts and her thoughts on integrating sUAS in their mission.

1. What sort of background/experience do you have related to conservation/biology?

My degree is in Wildlife Biology, 15 years of experience working with threatened and endangered species including gopher tortoise, red-cockaded woodpecker, flatwoods salamander, gopher frogs, eastern indigo snake, and sea turtles.


2. How much did you know about endangered marine turtle species before getting involved with Eglin?

Other than basic classroom information, not much at all.


3. What turtle species’ nest at the Santa Rosa Island and Eglin beaches?

In order of abundance – Loggerhead, Green, Kemp’s ridley and Leatherback.


4. Do you think Eglin’s efforts are making an impact on increasing hatchling numbers in general?

The sea turtle monitoring program follows a very specific protocol set by FWC that all sea turtle nesting beaches must adhere to. Volunteers and Natural Resource personnel spend countless hours monitoring nests for nearly 6 months every year. A lot of factors affect nesting and hatchling survival. Hatchling survival rate is definitely enhanced due to the remoteness and lack of human environment on Eglin’s beaches.


5. Had you considered using sUAS in this project before you were introduced to KwF and what sort of knowledge/experience do you have with sUAS?

No and very minimal knowledge before discussing this project with KwF.

6. What sort of impact do you think using sUAS will have on this mission?


That’s still to be determined with the approval of this project. The sUAVs will not replace volunteers or significantly reduce time or money spent monitoring sea turtle nesting activity. The sUAVs can potentially enhance our monitoring protocol.


7. Would Eglin AFB or Natural Resources (NR) consider integrating sUAS in other conservation projects?

Definitely a possibility. If the sUAVs prove to be as effective a tool as expected, then they could be integrated into additional conservation projects as needed.


8. Do you think endangered marine turtles can/will ‘bounce back’?

One can only hope they do.


9. What about the fate of other endangered species?

Eglin NR has been instrumental in the down-listing of the Okaloosa darter from endangered to threatened and in the increase of red-cockaded woodpecker breeding pairs from under 200 to nearly 450. Eglin NR personnel monitor several rare species to keep their numbers in check in an effort to prevent additional species from being listed.



FIG. 6 (right) Volunteer Rich Hardy roping off a sea turtle nest. Photo: Erica Laine of Eglin AFB/NR 2015

Fortunately, in the U.S. poaching is not an issue, however, at other reaches of the globe; the Indian Ocean specifically, Chinese and Vietnamese poaching vessels are easily and quickly traversing the waters. From egg to adult, all life stages of sea turtles are valuable on the black market for meat, curio and for use in traditional Chinese medicine. (WWF, 2015).

KwF’s second goal is to modify sUAS to seek vessels approaching shores, or poachers on natal beaches as well as illegal holding pens throughout the estuaries and hard to reach nooks and crannies all around the Coral Triangle and Kalimantan. Below is a map of poaching trade routes.

INTERVIEW 2

Dr. Nicolas Pilcher is marine biologist and CEO/founder of the Marine Research Foundation (MRF) in Malaysia. He holds a PhD in sea turtle biology and conservation and has spent the last 25 years working in turtle research and conservation. Dr. Pilcher tells me about their mission and the current poaching crisis.

1. What got you interested in working with sea turtles? Long story… I was working on a beach in Saudi Arabia when a turtle emerged missing a rear flipper. I ended up becoming the rear flipper and helped her nest three times that seasons and two additional seasons. Have been turtle-ing ever since.

2. What species’ do you specialize in?

None, and all… I have not worked with Kemp's but have dealt with all others. Most species I work with include green, hawksbill and leatherback.

3. Tell us about the IUCN SSC MTSG (Marine Turtle Specialist Group)

The MTSG is the body entrusted with determining Red List status for sea turtle species, and for setting global conservation priorities. It is a group of some 250 scientists and conservationists worldwide, bringing all levels of expertise to the table, and working collectively to determine ways forward for sea turtle conservation. I co-chaired the MTSG for 13 years until just a few months ago…

4. Tell us about how you began the Marine Research Foundation (MRF).

MRF is my excuse for not having a boss ☺ I set MRF up back in 2003 after being frustrated by wanting to work on turtle conservation but having bosses who did not get it. I had a few decent grants at the time and decided to go solo. We now have a couple of staff but that is it. We run projects in many countries, including Malaysia, Philippines, Qatar, UAE, Solomon Islands, Pakistan, and a number of others on shorter-term basis. Our main role is to find solutions to turtle conservation issues and make these available to governments and industries.

5. What is the MRF objective?

To provide science-based solutions to conservation issues. We strive to do the best science (relevant to the biology of the species in question) and translate this into conservation-relevant information.

6. What role do you play in anti-poaching missions, if any?

Not much of a role at all, really. When Co-Chair of the MTSG I helped lead a few missions to put a dent into the China/Vietnam poaching in SE Asia, and these appeared to be effective at the time. But the truth is the ‘war’ is not over and something needs to be done. I am not the activist and am extremely aware of my role as a foreigner in Malaysia and the limitations on what I can do. My interest is in developing the tools to help the local authorities do what they need to do to put an end to this.

7. How effective are current anti-poaching methods?

Partially. Malaysia has set up a series of radar control posts along its border, but we still get kidnapping and smuggling and poaching incidents right under the military’s noses. At present the largest issue is the fact that the problem has become as much an internal problem as an external one, with locals stockpiling turtles in anticipation of Chinese vessel arrivals.

8. Is anything being done to strengthen current efforts?

Not at present. There are limited resources, and more pressing issues politically.


9. Do you feel local governments/authorities could do more to curb/prevent poaching?

Absolutely, but I also understand government. They have funds to operate, but not to expand beyond their ‘zone’. If we can provide the expansion and the tools, maybe we can help drive their efforts into the areas that are really needed.

10. Do you feel the use of sUAVs could increase anti-poaching strategies?

I do, because of the low cost of operation and the large amounts of information the process would provide.

11. What do you think about the fate of endangered sea turtles? i.e. will we lose them/can they ‘bounce back’?

We won’t lose them due to this, but they won’t bounce back either. The problem is adult and large juvenile turtles are being targeted, which provide the backbone to the ‘bounce back’ effect.

12. If sea turtles were to become extinct in the wild, how do you think poachers would respond? i.e. what species would replace them on the black market?

Fortunately I don’t think they’ll go extinct. And therein lies the problem. The poaching won’t stop.

13. Anything else you would like to add?

Poaching is a complex issue as you well know – the market pressures that drive demand vary in time and space and are dependent on so many factors outside of the traditional biologists’ and conservationists’ control and spheres of expertise. But we can and should take those initial steps, rather than think the problem will solve itself. Poaching is not the greatest threat on the horizon for sea turtles – their biology has left them predisposed to deal with these sorts of pressures. But in order to see population recovery, it can’t be simply business-as-usual. It has to be more than that. If we were to leave natural mortality as just that – natural – we would never see an increase in a population over and above anthropogenic pressures. If we want to see that, we have to reduce all other levels of mortality, including those from poaching.


FIG. 8 (left) Dr. Nicolas Pilcher Photo: Keirsten Clark Photo: http://www.expatriatelifestyle.com/fromthemagazine/article/Expatriate-Profiles/Dr-Nicolas-Pilcher 2012





KwF strongly believes sea turtle conservation foundations, biologists, and anti-poaching groups can and will benefit greatly from using fully autonomous drones in their work. sUAS are NOT meant to replace current efforts, but to strengthen, modernize, and compliment them. KwF is looking forward to getting in the field, lifting our eyes to the sky, and digging our feet into the sand…literally.

For more information please visit

REFERENCES:


Defenders of Wildlife. (2015). Basic Facts About Sea Turtles. Retrieved July 2015, from Defenders of Wildlife: http://www.defenders.org/sea-turtles/basic-facts


GreenFacts.org. (2001). Retrieved July 2015, from GreenFacts.org: http://www.greenfacts.org/glossary/ghi/hearing-threshold.htm


GreenFacts.org. (2001). Retrieved July 2015, from GreenFacts.org: http://www.greenfacts.org/glossary/def/frequency.htm


IUCN. (1994). 1994 Categories & Criteria (version 2.3). Retrieved July 2015, from The IUCN Red List of Threatened Species: http://www.iucnredlist.org/static/categories_criteria_2_3#critical


Sea Turtle Conservancy. (1996-2015). General Behavior. Retrieved July 20, 2015, from Sea Turtle Conservancy: http://www.conserveturtles.org/seaturtleinformation.php?page=behavior#nest

WWF. (2015, March). Illegal Take and Trade of Marine Turtles in the Indian Ocean Region. Retrieved August 2015, from WWF Global: http://wwf.panda.org/?243870/Illegal-Take-and-Trade-of-Marine-Turtles-in-the-Indian-Ocean-Region#

WWF. (2015). Marine Turtle Overview. Retrieved July 2015, from World Wildlife Foundation: https://www.worldwildlife.org/species/sea-turtle

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