Course:CONS200/2023/Strategies for the conservation of loggerhead turtles in Zakynthos, Greece

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Loggerhead Sea Turtle (Caretta caretta) 2.jpg

Compared to all of the species of turtles that live in the ocean, loggerhead turtles have the hardest shells and biggest heads. These turtles weigh approximately, 200-300 pounds and have a length of 2.5 to 3.5 feet when mature. The average loggerhead has a life span from eighty to one hundred years, while comparatively, most females reach the stage of maturity at ages 35-45 years[1]. Loggerhead turtles do not have a specific location of origin as they a distributed worldwide from the Indian Ocean to the Mediterranean Sea and the Atlantic Ocean. They can also be found in small populations off the western coast of the Americas from Chile up to Alaska[2]. The preferred resting places are predominantly located in subtropical or temperate areas near coastal shorelines, as it is ideal for the female turtles to have easy, quick assess to nesting areas on beaches, as the average female turtle mates every 2-3 years[3]. Loggerhead turtles of all ages, primarily juvenile and mature, eat a variety of crustaceans and other small invertebrates as they can crush the shells of their prey due to their mighty jaws, which have a bite force of 500 pounds[4]. Some animals they feed on are whelks, mollusks, and various crab species [5]. Baby loggerhead head hatchlings have a mixture of a plant-based and soft animal diet, as their powerful jaws have yet to develop.

Global climate warming has induced changes that affect habitat quality leading to the expansion of species range and distribution. While the Mediterranean Sea has been a site for sporadic nesting there has been a noticeable increase in the nesting activity of loggerhead turtles since 2013 from 1-3 nests per year with 84 recorded in 2020. Zakynthos island located in the Ionian Sea to the west of Mainland Greece has been a crucial nesting ground for more than 80% of the adult female turtles who return to the beach and excavate a pit to lay eggs. However, Loggerhead Turtle Caretta caretta has most recently been assessed for The IUCN Red List of Threatened Species in 2015. Caretta caretta is listed as Vulnerable under criteria A2b[6]. Loggerhead turtles in Zakynthos are under threat due to the anthropogenic impact that is induced by the development of beaches for tourism. Increased pollution, traffic due to boats and fishermen and insufficient waste management poses a lot of challenges for nest relocation. Most female turtles lay eggs very close to the shore or in the dark to avoid the illumination of the nearby hotels and restaurants thus making them vulnerable to motion-induced mortality but recent increases in deaths and injuries have been due to being hit by boat propellers.

History

The loggerhead turtles of Zakynthos Greece have settled in this area since 1980 with their preferred areas of resign being in subtropical and temperate areas. They have historically been found in the Mediterranean Sea with overfishing causing their population decline. Loggerhead turtles have been around for a very long time, although they have some modern-day adaptions their ancestors can be tracked almost 50 million years ago through various fossil records. Loggerhead turtles are known for migrating to great lengths, and even to this day don't understand the reasoning behind their migration patterns[7]. Considering this vast area of migration they have resigned in different areas. With this have come many tales and symbols for the loggerhead turtles in First Nations communities. The First Nations of North America have said that loggerhead turtles are a symbol of strength and have been associated with the lifecycle as well as the earth[8]. In Mexico, they have believed that these turtles are the protectors of the sea, and believe that conserving and maintaining these turtles and their habitats is the key to the success of the ecosystem. In Australia and North America these turtles have been used as a food source as well as used in ceremonial practices, they as well believe the conservation of these turtles is significant to their culture and the ecosystem surrounding them[9].

Why You Should Care

Why should we care about the loggerhead turtle? Considering their long history in the wild and the roles they have played in the ecosystem they should be conserved as best as we can. Loggerhead turtles as mentioned before playing a role in First Nations culture and have also played a role in the public eye with their loveable appearance and likeability. They are a great tourist attraction and draw people to the shores of Zakynthos Greece [10]. Without these turtles and tourism, Zakynthos could lose money to put back into their city. Behind the visuals, symbols, tales, and their economic value, they as well play an important role in the ocean's ecosystem and its balance in food webs. Their diet consists of bottom sea floors creatures like crabs, sea urchins, and mollusks [11]. These sea creatures need to be eaten by the turtles or else their population would boom and cause harm to the seagrass beds and coral which the bottom dwellers' main diet consists of. By saving these animals we are saving more biodiversity in the ocean and allowing for ecosystems to run how they are supposed to, caring about the conservation of the loggerhead turtles is the first step to saving this beautiful creature which plays a role in the ecosystem, economy, and culture.

Assessment of the Effectiveness of Different Conservation Strategies

Example of in-situ conservation for loggerhead turtles.

Loggerhead turtles are a long-lived species therefore the stretched time period between their juvenile and adult stage makes it challenging to assess the population trends [12]. Conservation techniques in the past have focused on protecting the species at their juvenile stages considering that predation by animals is the leading cause of their decline. Strategies employed for conserving the populations include both in-situ and ex-situ conservation and other protection regimes such as building cages around nests to prevent predation[13]. The philopatric and migratory nature of the loggerhead turtles places high importance on in-situ conservation strategies because their populations return to their native habitats for breeding and reproduction[14]. Habitat management and restoration activities can increase connectivity between the habitats allowing ground for interbreeding and for promoting gene flow between the populations[15]. However, the anthropogenic impact that is induced by the increase in tourist activities has been challenging in achieving these desired conservation goals[16].

Ex-situ conservation implies conserving a species away from its natural habitat which has been a beneficial strategy for conserving loggerhead turtles especially when there are natural threats to in-situ incubation such as tidal inundation. There were many other notable benefits such as an improved immune configuration, greater body mass, and length corresponding to higher fitness like faster emergence from the nest and crawling to the sea[17]. Lower temperatures and higher humidity lead to an increase in the Spleen Somatic Index which can be an indicator of an improved lymphatic system and filtration of blood[18]. Apart from the high maintenance costs associated with research, monitoring, captive breeding, and re-introducing the species to their habitat, it is confirmed that ex-situ conservation biases sex determination to males. This could have negative implications leading to a decreased genetic diversity and imbalanced sex ratios[19] which could be a threat to population viability specifically for long-lived organisms.

 Protection treatments included self-releasing metal screens, metal cages and plastic cages made with mesh materials that allowed the hatchings to emerge from the nests[20]. This strategy has been found to be beneficial for eliminating predation by coyotes and increasing the number of hatchlings per nest. Using the criteria of the number of hatchings to evaluate the effectiveness of nest protection may prove it to be an extremely successful conservation strategy[21]. However, results have shown that only a small number of hatchings survive under this conservation strategy. Moreover, predation alone is not leading to their declining populations therefore the strategy of nest protection may not aid in long-term population recovery[22].

Future Conservation Efforts

Beach-clean activities as a form of ecotourism that builds environmental and cultural awareness to minimize the degradation of natural resources.

Considering that Zakynthos and Ionian islands have low employment rates, the development of the tourist sector can be extremely crucial to boost the revenues of the local economy[23]. However, the increased tourist activity has led to an increase in commercial fishing, plastic waste, and artificial lighting which has had a deleterious impact on biodiversity[24]. Light pollution is a potential threat for loggerhead turtles as it alters their nesting activity and reduces the survival chances of the new hatchlings. Nesting is a nocturnal activity and female loggerhead turtles prefer low/natural light conditions for laying eggs. Artificial beachfront lighting of hotels and restaurants typically results in the disorientation of hatchings that are extremely vulnerable both during their crawl from the nest to the sea and their initial swim away from the beach. Results have concluded that the increased brightness facilitated the movement of hatchings away from the ocean increasing their mortality due to predation.[25] An increased number of tourists has also resulted in an increase in human waste such as plastic bottles and disposable plates etc. which are ingested by 80% of loggerhead turtles at all stages of their life cycle [26]. Furthermore, both nesting loggerhead turtles and developed hatchlings can become obstructed and tangled in plastic at nesting sites which has increased their chances of predation. Surprisingly, these turtles are also having severe injuries and death. by being hit by boat propellors and getting stuck in the fishermen's nets[27].

Increased anthropogenic impact through modification of land use calls for more community-based approaches for conservation that not only leads to pro-environmental behaviour but also facilitate a learning experience of ecosystem functioning for the tourists. Community-based approaches such as beach cleaning can empower and educate tourists to understand the intrinsic impact of their day-to-day activities on ecosystem functioning[28]. The government can ensure that the boating companies are licensed and the professionals are aware of the speed limits near the shore and transition environments to prevent the degradation of microflora and microfauna. The government can also monitor and assess the impact of oil and fuel leakage to prevent water pollution[29].

Conclusion

Through different anthropogenic pressures, loggerhead turtles may have a future through extensive conservation efforts developed by humans. Such conservation efforts must be held accountable and maintained by the residents of Zakynthos Island in Greece if residents want marine biological life to prosper. As these turtles are declining in numbers at a fast rate strategies such as reducing the number of tourists visiting the areas during nesting season, reducing boat activity and cleaning up garbage in marine areas are some ways to help conserve loggerhead turtles. With these strategies, laws must be instituted and must go into effect to maintain a stable marine environment. The future is still bright for leatherback turtles if the right/proper actions are taken.

References

Please use the Wikipedia reference style. Provide a citation for every sentence, statement, thought, or bit of data not your own, giving the author, year, AND page. For dictionary references for English-language terms, I strongly recommend you use the Oxford English Dictionary. You can reference foreign-language sources but please also provide translations into English in the reference list.

  1. ↑ Şirin; et al. (2021). "Age structure of stranded Loggerhead Turtles (Caretta caretta) in Turkey". Zoology in the Middle East. 67. Explicit use of et al. in: |last= (help)
  2. ↑ Bowen; et al. (April, 1995). "Trans-Pacific migrations of the loggerhead turtle (Caretta caretta) demonstrated with mitochondrial DNA markers". Proc Natl Acad Sci USA. Explicit use of et al. in: |last= (help); Check date values in: |date= (help)
  3. ↑ Sönmez, Bektaş (May, 2021). "Nesting activity of loggerhead turtles (2013–2020) and 20 years abundance trend (2001–2020) on Çıralı Beach, Turkey". Regional Studies in Marine Science. 44. Check date values in: |date= (help)
  4. ↑ Pfaller; et al. (February, 2010). "Ontogenetic scaling of cranial morphology and bite-force generation in the loggerhead musk turtle". Journal of Zoology. Explicit use of et al. in: |last= (help); Check date values in: |date= (help)
  5. ↑ Mariani (February, 2023). "Dietary Preferences of Loggerhead Sea Turtles (Caretta caretta) in Two Mediterranean Feeding Grounds: Does Prey Selection Change with Habitat Use throughout Their Life Cycle?". Animals (Basel). Check date values in: |date= (help)
  6. ↑ "Loggerhead turtles". IUCN.
  7. ↑ McClellan; et al. (2007). "Complexity and variation in loggerhead sea turtle life history". Explicit use of et al. in: |first= (help)
  8. ↑ Dabrowski, María. "Sea Turtle Folklore and Traditional Ecological Knowledge".
  9. ↑ Kuhnlein; et al. "Traditional Animal Foods of Indigenous Peoples of Northern North America". Explicit use of et al. in: |first= (help)
  10. ↑ Warren; et al. (July, 2009). "The conservation of loggerhead turtles in Zakynthos, Greece". Orxy. Explicit use of et al. in: |last= (help); Check date values in: |date= (help)
  11. ↑ Parker; et al. (2005). "Diet of oceanic loggerhead sea turtles in the central north pacific". Explicit use of et al. in: |first= (help)
  12. ↑ Pietroluongo et al., 2023. "Environmental and pathological factors affecting the hatching success of the two northernmost loggerhead sea turtle (Caretta caretta) nests". Research Gate.
  13. ↑ Kornaraki et al., 2006. "Effectiveness of different conservation measures for loggerhead sea turtle (Caretta caretta) nests at Zakynthos Island, Greece". Biological Conservation.
  14. ↑ Haywood et al., 2020. "Spatial ecology of loggerhead turtles: Insights from stable isotope markers and satellite telemetry". Diversity and Distributions.
  15. ↑ Marn et al., 2017. "Environmental effects on growth, reproduction, and life-history traits of loggerhead turtles". Ecological Modeling.
  16. ↑ Maxwell et al., 2020. "Area-based conservation in the twenty-first century". Nature.
  17. ↑ Robledo-Avila et al., 2022. "Short communication: Ex-situ conservation in hatcheries is associated with spleen development in Lepidochelys olivacea turtle hatchlings". Science Direct.
  18. ↑ Bao et al., 2009. "Architecture of the blood-spleen barrier in the soft-shelled turtle, Pelodiseus sinensis". PubMed.
  19. ↑ (Angrist, 2000). "Consequences of Imbalanced Sex Ratios: Evidence from America's Second Generation". National Bureau of Economic Research.
  20. ↑ Mnr et al., 2019. "Do Wire Cages Protect Sea Turtles from Foot Traffic and Mammalian Predators ?". Sematic Scholar.
  21. ↑ Hatch et al., 2022. "Estimating the complex patterns of survey availability for loggerhead turtles". The Journal of Wildlife Management.
  22. ↑ Campbell et al., 2020. "The efficacy of protecting turtle nests as a conservation strategy to reverse population decline". Biological Conservation.
  23. ↑ Kapsaski et al., 2015. "Planning the Sustainable Tourist Development of Zakynthos Island: A Methodological Framework". Cultural Tourism in a Digital Era.
  24. ↑ Davis, 2019. "Human Impact on Coasts". Encyclopedia of Earth Sciences Series.
  25. ↑ Colman et al., 2020. "Assessing coastal artificial light and potential exposure of wildlife at a national scale: the case of marine turtles in Brazil". Biodiversity and Conservation.
  26. ↑ Wilcox et al., 2018. "A quantitative analysis linking sea turtle mortality and plastic debris ingestion". Scientific reports.
  27. ↑ Carreño & Lloret, 2021. "Environmental impacts of increasing leisure boating activity in Mediterranean coastal waters". Ocean & Coastal Management.
  28. ↑ Brooks et al., 2013. "Assessing community-based conservation projects: A systematic review and multilevel analysis of attitudinal, behavioral, ecological, and economic outcomes". Environmental Evidence.
  29. ↑ Carreño & Lloret, 2021b. "Environmental impacts of increasing leisure boating activity in Mediterranean coastal waters". Ocean & Coastal Management.

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Note: Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in Wikipedia: Writing better articles.[3]

  1. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named :1
  2. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named :0
  3. ↑ En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].


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