• Sustainable Palm Oil and Barn Owls

Sustainable Palm Oil and Barn Owls

By Shakinah Ravindran & Hasber Salim.
With input from the Barn Owl Trust, Devon, UK.

Palm oil has grown into a global commodity since its first commercial plantations in the 1920s. In 1980, the world produced four-and-a-half million tonnes of palm oil and nearly 15 times as much in 2014 (Meijaard et al., 2018). Its high yield, versatility, and relative low cost have led to its wide use. However, like most monocultures, the oil palm industry comes with its drawbacks to the environment. Among its major issues are environmental pollution, deforestation and biodiversity loss. On a global scale, oil palm development causes less than 0.5% of all deforestation, but in parts of the tropics this can be up to 50% (Meijaard et al., 2018). Indonesia and Malaysia are the leading palm oil producing countries, and this region contains 11% of the world’s remaining tropical forests (Iremonger et al., 1997). Oil palm plantations have been listed as a threat to 405 species globally, of which 193 are listed as Critically Endangered, Endangered or Vulnerable (Meijaard et al., 2018). Published literature also reports that species richness of invertebrates and vertebrates are lower in oil palm plantations compared to primary forests, logged forests and other tree crops.

There are various ways of defining oil palm sustainability; broadly there are economic, social and environmental aspects. In terms of biodiversity, sustainable palm oil production requires that plantation growers no longer perpetrate or perpetuate deforestation, thereby helping to protect rare and endangered species, as well as high biodiversity value areas. Attempts to address the complex and numerous issues concerning social and environmental impacts throughout the palm oil supply chain have resulted in a wide range of initiatives; one example is the voluntary certification of more sustainable production. The most widely used global standard is the Roundtable on Sustainable Palm Oil (RSPO). The RSPO produces a Certified Sustainable Palm Oil (CSPO) certificate, which is issued to companies that comply with a set of environmental and social criteria developed by the RSPO that consists of 8 operating principles and 39 criteria. A noteworthy criteria of these certification bodies is the protection of High Conservation Value (HCV) areas. The RSPO criteria relating to this states that “…no primary forests or areas which contain significant concentrations of biodiversity (e.g., endangered species) or fragile ecosystems, or areas which are fundamental to meeting basic or traditional cultural needs of local communities (high conservation value areas), can be cleared.” Strategies such as these are useful guidelines for forming ‘wildlife-friendly’ management in oil palm plantations, although their overall effectiveness has not been widely demonstrated and there is call for a more precise definition of HCV areas.

There are other global certification standards used by the oil palm sector, such as the Rainforest Alliance Sustainable Agricultural Standard, which is considered one of the most stringent certification standards for biodiversity protection. There are also national certification standards bodies, such as Malaysian Sustainable Palm Oil (MSPO). The MSPO is the Malaysian version of RSPO, issued by the Malaysian Palm Oil Certification Council (MPOCC), and is based on 7 principles that include protecting the environment, natural resources, biodiversity and ecosystem services, and following guidelines for the development of new plantations. It was recently made mandatory for oil palm plantations and mills, and independent and organized smallholders without RSPO certification to obtain MSPO certification by the end of 2019. Additionally, a MSPO-RSPO Working Committee was formed to develop and produce an auditing checklist as well as a systems comparison document for conducting combined MSPO-RSPO audits for plantations and mills. In regard to the MSPO, though new plantations are obliged to avoid planting on land with high biodiversity value, this is still allowed if it is carried out in compliance with national and/or State Biodiversity Legislation. Despite this, we maintain that high biodiversity areas should not be cleared and that plantations need to adjust their development plans, whether in relation to opening new plantations or expanding existing land, in order to protect high biodiversity value areas. Additionally, the MSPO should explain clearly under what legislation/guidelines clearing is allowed.


Seventy-five percent of global palm oil production goes into food products, particularly cooking oil and processed oils and fats, while a smaller percentage is utilized as biodiesel fuel for cars and power plants (RSPO). There are various organizations aiming to promote sustainable palm oil awareness among consumers. An example of a global group is the Global Alliance for Sustainable Palm Oil (a collaboration with San Diego Zoo Global, Uganda Wildlife Education Centre, Wildlife Reserves Singapore, Zoos Victoria and Bristol Zoo Gardens), whose objectives emphasize creating a behaviour change among consumers to seek out sustainable palm oil. On a national scale, the Sustainable Palm Oil Movement (SPOM) in Malaysia aims to create awareness that palm oil in itself is not the problem, rather the associated practices are, and that these should be the focus of improvement. Oil palm plantations are not going to go away in the foreseeable future, but one thing we can do now is practice conscious consumerism by purchasing products containing sustainable certified palm oil. Indeed, in recent years the rising recognition of biodiversity-friendly oil palm plantations has been primarily motivated by environmentally conscious consumers who demand agricultural products produced in an environmentally sustainable and socially responsible way. Consumers should be aware that simply boycotting all palm oil products is unfruitful, as certified palm oil consists of palm oil that adheres to sustainable guidelines, such as no primary forest clearance. Responsible consumerism is only part of the solution, but a halt to the consumption of uncertified palm oil products in necessary. Boycotting uncertified palm oil products puts pressure on manufacturers and producers to change their practices in order to be compliant with guidelines and become eligible for sustainability certification.

 

In this context, we wish to highlight rodenticide use and Integrated Pest Management (IPM) in oil palm plantations. IPM is one of a suite of sustainability measures in oil palm plantations which can be discussed in terms of economic and environmental impacts. Rat populations in oil palm plantations can cause between 5 and 10% loss of oil, which with varying palm oil price can lead to a potential financial loss from 48 to 288 USD per hectare (in recent years this meant a range of 200–600 USD/t; Wood & Chung, 2003). Control of rat pest populations is typically with rodenticides, specifically anticoagulant rodenticides. In 1984, Wood and Liau quoted a cost of £48/ha for the 240 kg of oil lost annually; but control with warfarin baits led to loss of only £3-4.5/ha. More recently, CM Rizuan et al. (unpublished) reported that fresh fruit damage (fresh fruit damage is shown in the image on the right) during monthly assessments ranged from 0.0% to 32.44% in plots where rodenticides were applied. 

WhatsApp Image 2019 11 07 at 12.40.28OP damage by rats 

Common rat species in oil palm plantation, Rattus tiomanicus, (left) and frest fruit bunch damage by rats (right) 

When it comes to addressing the issue of rat pests, barn owls (Tyto javanica javanica) (pictured below) are frequently featured in IPM. The Malaysian Palm Oil Board actively promotes barn owls as part of the sustainable control of rat pests (typical rat pest species in oil palm plantations, Rattus tiomanicus, pictured on the left) and encourages the propagation of barn owls to control rats in oil palm plantations. This positive action is used to fulfil one of the growers’ principles of the RSPO: “to protect, conserve, and enhance ecosystems and the environment” (Principle 7) and RSPO Criterion 4.5: “Pests, diseases, weeds and invasive introduced species are effectively managed using appropriate Integrated Pest Management techniques” according to national guidelines. There is, however, some disagreement about the efficacy of barn owls as a rat control agent, not least because it is difficult to make a comparative evaluation between reports (Wood & Chung, 2003). Several studies report that barn owl populations have resulted in lower rodent damage and numbers (e.g., Chung et al., 1995; Ho & Teh, 1997; Heru et al., 2000). In contrast, other studies report that barn owl occupation appears to have no clear effect on rat populations (Chia et al., 1995) because the owls are unlikely to have a significant impact in high infestation areas, where rat reproductive rates far exceed barn owl predation rates.

In most plantations, encouraging barn owls is typically implemented alongside complementary baiting. Pesticide use is covered in both RSPO and MSPO criteria (e.g. RSPO Criterion 4.6: Reduction in use of pesticides), but stricter guidelines need to be in place when barn owls are implemented as biological control agents alongside complementary baiting. This was a less pressing issue in the early years of the industry, when less toxic, first-generation rodenticides were applied. However, following widespread resistance among rats, chemical control shifted to favour highly toxic second-generation rodenticides. Both first- and second-generation rodenticides pose a threat to non-target species and there has been a wide array of non-target poisoning reported in birds (raptor and non-raptor) and mammals (e.g., Erickson & Urban, 2004; López-Perea et al., 2019). Rodenticides have also been detected in invertebrates, fish, and reptiles (e.g., Pitt et al., 2015; Lettoof et al., 2020). Barn owls in oil palm plantations mostly feed on rats, making them especially vulnerable to secondary poisoning. This can lead to death in young and adult owls, as well as deformities in young owls (Salim et al., 2016). In large oil palm plantations, campaign baiting is typically carried out by applying rodenticides one or twice a year, depending on results from a rat population census. However, this application strategy is replaced by fixed baiting campaigns when there is high damage during rat infestations, leading to higher numbers of barn owls exposed to secondary poisoning.
As oil palm companies typically include data on local barn owl populations to fulfil the criteria of sustainable practices, sustainable certification bodies should introduce stricter guidelines on rodenticide use in relation to local barn owl populations. An alternative to using second-generation rodenticides would be the use of first-generation rodenticides, which have a relatively lower toxic effect. Another step, albeit much harder to achieve, is a perception shift among oil palm players from focusing on the complete eradication of rats to managing the population to an acceptable level. After all, complete removal of the rat population would not be sustainable to the barn owl populations in plantations. Plantations should work to maintain the rat population to a threshold level of <5% damage to crops, i.e. there should be no chemical rat control unless damage to crops is higher than the threshold level. Annual fixed baiting campaigns should be replaced with the census-and-bait method, which is where a census on the rat population is carried out to assess damage and baiting only proceeds when damage is above the critical level. This would not only reduce the cost of baiting, but also prevent the build-up of tolerance among the rat population. These two simple steps would not only reduce secondary poisoning of barn owls and non-target species, but also reduce the poisoning to other non-target species that directly consume baits found on plantation grounds.

References
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