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Bat Fatalities At Kahuku Windfarm: Making A Case Under International Environmental Law


The fate of hundreds of endangered hoary bats was at the forefront of proceedings before the Hawaii Supreme Court in a case that dealt with halting operations of a contentious wind farm in Kahuku and lifting the stakes for other renewable energy ventures in Hawaii. This came into light after a growing community opposition towards introducing numerous clean-energy projects in the state. The community pleaded to send back the habitat conservation plan – a state-approved document outlining how the developer intends to mitigate the killing of bats for reconsideration. In addition to this, it was also contended that the plan did not follow the set standards by the legislation to protect endangered species, which allows the turbine to kill 51 bats over the years.

Understanding how the windfarm can harm the bats

Before further deliberations, it needs to be understood that the rapid expansion of wind energy is an important step towards reducing dependence on non-renewable sources of energy. However, wind energy is not entirely environmentally friendly, as wildlife and ecosystem impacts have been reported and are a growing source of concern. Wind energy development directly affects the environment and has indirect effects on the structure and function of the ecosystem. There have been studies that establish that wind turbine negatively impacts the bats and cause bat mortality. There are various reasons which cause bat mortality around wind turbines. The location of the wind farm is one of the variables which attracts the bats. Even at low wind speeds, the collision of bats and rotating blades is a chance event. Bats are likely attracted to turbines in one of two ways: directly because turbines simulate roosts, or indirectly because turbines attract insects that bats consume.

International regimes governing the protection of bats

Owing to the above implications on wildlife, there have been numerous international treaties and conventions with the principal aim to provide direction and coordination for the conservation and protection of bats across the globe. For example, Article 5 of the Convention on Biological Diversity mandates the states to conserve and protect biodiversity within their territory. Moreover, Article 8 provides guidelines for their management and establishment, and states must be obligated to manage their biological resources to promote the recovery of threatened species both in and outside protected areas.

EUROBATS is another international treaty that deals with the protection and conservation of bats across territories of State Parties. Article 3(1) of EUROBATS requires states to prohibit the deliberate killing of bats, while states are also required to protect bat species that are under threat, including threats posed by wind turbines. As a result, states have a responsibility to consider bats in turbine planning processes, along migration paths, and in other places of importance to bat populations. Further, the Convention on the Conservation of Migratory Species explicitly states under Article 2(1) that it is mandatory to pay special attention to migratory species the conservation status of which is unfavourable and in co-operation and take necessary steps to conserve such species and their habitat.

Furthermore, the Precautionary Principle (PP) is a well-recognized part of customary international law. According to customary international law, where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing measures to prevent environmental degradation. The above Principle is recommended to avoid the negative impacts of climate change mitigation activities on biodiversity. Due to the irreversible nature of fatalities, Precautionary Principle ought to be observed through mitigation where bat fatalities are high, such as at wind farms. States wishing to undertake activities that threaten the environment are obligated to prove otherwise. The most significant impact of operating wind turbines on bats is a direct killing caused due to collision/head-force trauma and/or barotrauma. In the present case, it is seen that the Board of Land and Natural Resources has granted a license to kill about 51 opeapea, also known as hoary bats, over the course of 20 years. This board decision can negatively impact the population of bats and expose the bats to a threat of harm. Further, the Hoary bats are listed as endangered species and vulnerable species under federal & state laws and by US Fish and Wildlife services. Additionally, the hoary bats contain a low reproductive rate which adds to the vulnerability of the species. Hence, it has been proved that any increase in the mortality rate could be critical and therefore, the harm is irreversible in nature.

Suggestions and Conclusion

In light of the above conventions and treaties, it becomes important to implement appropriate mitigation measures to restrict bat mortality at the Kahuku Windfarm. Since bats are present almost everywhere and bat mortality at wind turbines has been documented in almost all forms of landscapes, it is evitable this Kahuku wind farm projects may affect bats. As a result, before granting approval for a proposal or project, relevant authorities awarding licenses and regulations on environmental requirements for US wind energy developments should entail an adequate risk assessment for bats. An impact assessment aims to evaluate potential effects on local and migration bat species and develop site-specific avoidance or mitigation measures and monitoring programs. Currently, in the present case, it has been reported that specific mitigation measures, including habitat restoration and research, have already been budgeted. However, the same seems inadequate considering the level of risk associated with the endangered species. Thus, the current situation demands the government agencies to place a moratorium on industrial wind turbines to give the endangered species a fighting chance at survival considering the above-mentioned treaties, conventions, and principles of international law. Regarding the enforcement mechanism, the CBD provides for the enforcement mechanism within the Convention itself, which includes a clearing-house mechanism to facilitate technical and scientific cooperation. The compliance mechanism has been given under the Cartagena and Nagoya Protocol. Furthermore, under EUROBATS, the enforcement plan is directly given under the EUROBATS action plan. However, the enforcement mechanism given in the treaties are very difficult to be implemented with the difficulties of enforcing the compliances across borders with local legislation and with USA not signatory to the treaties, it becomes more difficult to implement those treaties.

Akshat Kothari is a 3rd Year law student pursuing B. Com LLB from the Institute of Law, Nirma University. Akshat has a keen interest in the field of Public International Law, International Environmental Law and International Business Law.


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