Key elements required for the effective translation of science into conservation action

Policy is the most effective vehicle for conservation solutions to be implemented; one of the main aims of conservation science, therefore, is to provide data which can be translated into policy. The translation of science into policy is a challenge, made more difficult by the increasingly global nature of the threats faced. It is therefore important that scientists strive to include certain key elements in their work which makes the translation into policy more likely. I argue here that there are five key elements which increase the translatability of science into conservation policy: evidence, relevance, practicality, collaboration and long-term mind-set.

1. Evidence: Strong scientific evidence

2. Relevance: Focussing on issues that are relevant to policy makers, economically and

3. Practicality: Policy must take into account ethical/ cultural considerations to make it practical

4. Collaboration: Scientists must develop relationships with policy makers

5. Long-term mind-set

These key elements work to ensure that the scientists and policy makers contribute successfully to conservation policy. With estimates that only 30% of all previous conservation policy has yielded successful outcomes, it is imperative that these elements are understood and incorporated into the scientific and policy making process in order to produce more successful outcomes.

1. Evidence: Strong scientific-evidence

Strong scientific evidence is a key element in the translation of science into conservation policy as it is otherwise ignored or leads to poor policy decisions. The science should be conducted using iterative methods (Figure 1) which highlight and focus on monitoring both during the study and afterwards; the science component of policy making should not stop once the policy has been made. An instance where monitoring has stopped and consequently led to failure of a conservation policy is the instance of Saiga-Antelope in Kazakhstan. In the early 1990s governments encouraged Saiga hunting as a means to protect native rhinos as their horns were an alternative medicinal-product. Following the collapse of the Soviet Union however, monitoring of Saiga populations ceased, but the hunting did not, resulting in a 97% decline in the population. Examples such as this demonstrate the need to maintain scientific activity despite policy being in place to maintain the success of conservation policies.

Given the fact that not all scientists follow robust scientific procedure as described above, one solution to contribute to a more successful policy is a systematic review of the literature; used in order to gain a wider perspective than a single study (Figure 2). These reviews evaluate/weight studies according to the strength of evidence they offer, proportional to the study size and rigour. This can be demonstrated by the instance of the alarmist paper on insect declines published in 2019 by scientists who were un-educated on the issue (Sanchez- Bayo), claiming that 40% of insects may be extinct in the next few decades. At least seven papers were published challenging this method and conducting independent literature reviews which demonstrated the absurdity of the claims. If policy was based on this type of science, it would lead to negative outcomes and reduced scientific confidence. It is important therefore that the science is reviewed and robust to ensure it is well translated into policy.

2. Relevance: Focussing on issues that are relevant to policy makers

Whilst scientific integrity is vital to gain the attention of policy makers, if the science is not relevant to something with a solution in policy, it is not translatable. One of the overarching features of science which often influences policy is that it has an anthropocentric view; presenting science in a which demonstrates direct impacts on humans is more likely to be included in policy. This can be demonstrated by the popularity of ‘ecosystem services’-based papers in articles including COP25 and IPCC reports. Ecosystem services relate directly to what the environment provides for humans. One instance where policy has failed due to lack of anthropocentrism is in major international interventions to stop whaling in Japan; due to the fact that there are no measurable ecosystem-service consequences of removing whales, there is little incentive for governments to act to stop it. Presenting the science in an anthropocentric way is therefore a key element to translating the science into conservation policy.

3. Practicality: Policy must take into account ethical/ cultural considerations to make it practical

Another way in which science has not been effectively translated into conservation policy historically is through lack of practicality; scientists have often not been sensitive to global situations, leading to them suggesting changes which are not compatible with communities, and therefore unlikely to be incorporated into policy. An example of where failure to understand local culture has led to conservation policy failure is the case of policy in the Ba-Vì-National-Park, to reduce footfall to reduce impacts on biodiversity; this policy emphasised conservation at the expense of local livelihoods, leading to corruption as local officials colluded with National-Park authorities to monopolise resources and control villagers. The land became a site of conflict between villagers, local-officials and government and no measurable changes to the impacts on biodiversity. It should therefore be key in the translation of science to policy that practical considerations are made, including local interests being included in the design and implementation of policy.

4. Collaboration: Scientists must develop relationships with policy makers

Thus far, I have discussed key elements which are mainly the responsibility of the scientists, however, policy makers too are essential to the successful translation of science into policy; a relationship between the scientific and policy making parties should be developed. In instances where international governments are involves, collaboration becomes increasingly important. This can be demonstrated by the efforts of the RSPB in Syria, to protect the Sociable-Lapwing. Nest-monitoring and ringing-experiments showed a decline in the bird population, and the cause was determined to be hunting activity, taking place in Syria, during the Lapwing’s migration to Europe. In a country with political challenges such as war, governments are often less sensitive to conservation issues. Relationships with officials are therefore instrumental in the efforts to getting science into policy. This instance was successful, with education including an Arabic version of information pages on the birds contributing to its success. In this way, the relationships and personal understanding contributed to the success, demonstrating that collaborations are key in the translation of science into policy.

5. Long-term mind set

A key element which underlies each of those described above is that they must all maintain a long-term perspective to ensure success. Short-sightedness leads to discount-value mindsets and is unlikely to achieve sustainable outcomes. An example of where having a short- sighted mindset has led to conservation policy failure is the case of governmental support of oil palm as a substitute for other fuel- and food-products following scientific suggestions of biofuel effectiveness. This lacked long-term mindset as there was little consideration of how this policy could lead to expansion. The increased popularity of the product in European countries led to wide-scale agricultural expansion/intensification using unsustainable techniques. These impacts extend to 81% losses in forest species in oil-pall plantations (Fayle et al 2009), as well as >90% loss of regional Orangutan habitats. These failures highlight how essential it is that scientists and policy makers think with a long-term perspective to successfully translate science into conservation policy.

Whilst here I have considered mainly the direct translation of science into policy, there are alternative ways in which science can lead to policy change. Conservation groups such as Green Peace and WWF; these groups have translated the findings of scientific studies into campaigns to influence international treating and conventions such as COP-climate-conferences. Their efforts are based on science, and by gaining substantial support from the public, they are able to put pressure on governments to change. An example of success through these techniques is the WWF-Virunga campaign, which successfully lobbied for the banning of oil-extraction in the Congo and contributed to a number of policy changes regarding resource extraction in protected reserves across Africa. These uses of science can therefore also contribute to successful translation into policy, although are less used.

In conclusion, the key elements required to make science translatable into policy are ultimately context dependent; solutions should not be prescriptive with which elements are needed or how they should be achieved. Nevertheless, ensuring that the scientific evidence is strong, suggested changes are relevant and practical and that there is effective collaboration between scientists and policy makers with a long-term perspective, are key elements which will contribute to increased translatability. With so few conservation-based policies having succeeded historically, compounded by the fact that threats to conservation are increasing, it is important that substantial efforts are made to increase the successful incorporation of science into policy. Recent papers highlight the importance of politics in conservation (Cabin 2018), suggesting that increasingly, values and politics underlie environmental issues and scientific inquiry may be inherently unsuitable to resolve these issues; the future success of conservation might instead depend on more political than scientific progress; re-iterating the importance of effective translation of science into conservation policy.

How can fossil data be used to inform conservation decisions, and how do ecometrics contribute?

The majority of environmental challenges faced by conservationists contemporarily, have precedents in the past. Importantly, the fossil-record and associated long-term-environmental archives can provide unique insights towards the resolution of these challenges, especially concerned with understanding ecosystems prior to anthropogenic impacts; insights which have spurred the use of Paleobiology in conservation. Fossil data contributes to the biggest conservation questions including:

i) What should be conserved?

ii) Identification of species at risk

iii) Identification of thresholds

Underlying all of these conservation issues is the goal of enhancing adaptive capacities of ecosystems, increasing connectedness and improving functional integrity. These goals require a functional understanding of ecosystems, which can be achieved using ecometric analyses, this is a taxon-free trait-analysis studying the distribution of functional traits, and the environmental sorting of those traits, enabling predictions for the future based on current changes. I argue that perhaps the most important aspect shown by the fossil record is how novel modern ecosystems are; species are under pressure from a unique combination of threats not replicated in the historical-record, and in this regard, responses are somewhat unknown. This considered, conservation decisions should reflect the fact that we should not be trying to replicate historical conditions, but instead, with the use of ecometric-knowledge we should create functionally-intact novel ecosystems.

i) What should be conserved?

A major way in which the fossil-record can be used to inform conservation decisions is by providing evidence to indicate whether conservation should aim towards creating ‘novel’ or ‘historical’-systems. Historical-ecosystems are those which are operating as they have for centuries compared to novel eco-systems which are new in the ‘Anthropocene’. In order to decide the state an area should be conserved in, fossil data is used; this involves taxon-based (involving comparisons of taxa presence) and taxon-free (reflecting ecosystem function)-measures. Taxon-based-studies comprise of superimposed, well-dated fossils to produce snapshots of the past, allowing data on abundance and species-fluctuation to be analysed. One example where this is used was the re-introduction of wolves into Yellowstone; fossil-evidence showed that wolves had inhabited the region for>3000 years, this was given additional climate-context through pollen-studies, which indicated that the local climate had not changed significantly for>8,000 years. These findings supported the conservation of the area in its historical-state; leading to the successful re-introduction of wolves.

The alternative conservation decision; creation of a novel-systems, is also informed by fossil data. This is exemplified by the conservation strategy to protect Joshua trees in California. Fossil evidence in the form of Shashta-ground-sloth dung has shown that the tree is historically sensitive to increases in temperature. Given both the projected climate-change in the region as well the extinction of the ground sloth, its main seed disperser, the tree would is projected to go extinct in the region by 2070 without conservation action (Sweet et al 2019). These findings led to the conservation decision that a more active-management strategy is required. In this way, fossil data has led to effective conservation decisions.

In novel ecosystems, ecometric-analyses are often more applicable due to taxon-free metrics relating to environmental parameters with a degree of statistical-significance. This provides an opportunity for modelling the type of species which are likely to thrive in a region. This has been done on a large scale by Svenning-et-al-2017; this study models historical megafaunal distributions and compares these to modern climactic conditions to create a map where introductions of megafauna including mammoths, horses and hippo species could be re-introduced. Advances on these models include the suggestion of functionally-similar species to mammoth in the UK considering that mammoths went extinct ~14,000ya regionally; Monbiot has argued in numerous papers for the benefits that would confer to the habitat, including nitrogen turnover and positive impacts for agriculturally important insects. These somewhat drastic suggestions are supported by ecometric data which shows that the tooth of the elephant is compatible with the foliage in the remaining wild forests of the UK, and their temperature thresholds are similarly compatible (Ukkonen-et-al-2011). These re-wilding-conservation-projects currently rely on climactic parameters alone to estimate niche space; paleontologically-enhanced species-distribution-models would be helpful for the relocation or introduction of species into suitable-environments.

Given the unique and intensifying threats to modern ecosystems, novel ecosystems are likely to become more important as a conservation strategy; ecometrics should therefore be increasingly used to inform how these novel-ecosystems can be made to be functionally-intact and sustainable using historical-information. This is especially relevant in the land-sharing/ land-sparing-debate. Considering the combined impacts of increasing population and food demand, it is estimated that without significant yield intensification cropland will require an additional 600million hectares by 2050. This is relevant to this discussion because, in line with these predictions, policy changes starting in the UK with the environmental-Bill and suggestions from IPCC-reports, (promoting land-sparing strategies in agriculture), there will be increasing land-use-mapping which are expected to segregate land-uses more extensively; limiting regions for wild-life further. Ultimately, an earth split between a)agriculture b)urban-landscapes and c)wildlife/carbon-storage is what these policies seem to be moving towards. If this vision is realised, conservationists will be asked to protect as much biodiversity as possible in limited-regions; the resulting-collections of species may be entirely unique, yet functionally-sound if ecometric-models and historical-data are well collated. Although radical, these anthropocentric factors must be taken into account. Ecometrics and insights from fossil-data have the potential to make these drastic conservation decisions better informed and more likely to succeed.

ii) Identification of species at risk

In addition to contributing to conservation decisions on the state being conserved, fossil evidence informs conservation decisions at a species-level; identifying species traits which predict their survival in changing conditions. One example of this is data on mass-extinctions during the Permian-Triassic transition, where feed-back-loops from trap-volcanoes caused CO2 levels to rise similarly to current conditions. Fossil analysis coupled with biochemical knowledge indicates that the CO2 tolerant species were much more likely to survive this period than CO2-intolerant species- with a 38%-extinction compared to 81%-extinction in CO2-intolerant (Knoll-et-al-1996). This fossil information can be extrapolated to present conditions, predicting higher survival-potential for CO2-tolerant-species; perhaps indicating that more conservation action should be focussed on protecting CO2-intolerant-species. These functional-trait based analyses show the relevance of ecometrics to current-conservation challenges.

An emerging area of ecometrics is the study of historical-symbiotic-interactions and their responses to climate-change. Pither-et-al-(2018) study an ice-core containing evidence of the nitrogen-fixing-ectomycorrhizal-fungi and associated flora in New-Zealand. This eDNA-fossil analysis studied the interaction over 50,000years in relation to climactic changes. The study concludes that the symbiotic-relationship was negatively impacted by increased-temperatures. This aligns with Steidinger-et-al-2019, where the historical-symbiotic relationships’ interaction with climate is considered in the context of current-climate-change; the model suggests that changes in the Northern-Hemisphere could displace ectomycorrhizal-fungi to other regions, leading to a potential 60%reduction in the density of dependent trees. These outcomes would affect nutrient cycling and carbon fixation significantly and should be considered in carbon-based conservation initiatives. Identification of these relationships at risk using ecometric data can therefore guide conservation decisions by demonstrating potential threats to ecosystem-functioning.

Fossil evidence is imperative in niche-modelling to analyse the adaptive-capacity for individual species or populations. The adaptive-capacity of a species will determine the conservation strategy used; using fossil-data to discern the fundamental-niche of a species can indicate the adaptive-capacity of the species. One example of niche modelling compares the fundamental and realized niche of the three toes sloth (Philips-et-al-2017). This study produces MAXENT-models based on BIOCLIM-19-parameters. The results limited to modern-data could be expanded using hindcasting-techniques as current niches may not represent the total ecological-flexibility of taxa. McGuire-and-Davis-(2013) show how hindcasting using fossil-data can expand on knowledge using only modern-data; distribution-information from fossils of five-Microtus-species in the United-States were projected onto alternative-climate-surfaces, finding that the range of these species has undergone significant contraction since the last-glacial-maximum, and their predicted range tolerance is much larger than current-data would suggest. Accordingly, fossil-based niche-analysis can better inform adaptive-capacities, helping to identify species which should be conservation priorities.

iii) Identification of thresholds

On a wider scale to these niche-level applications, fossil and ecometric data are pivotal in the determination of environmental-tipping-points. Mathematical comparisons between fossils in lake-sediments, diatoms/pollen from Yunnan in China and regional ecological state shifts indicates strong correlations. In light of these results, it is clear to see how inter-disciplinary modelling projects which use paleobiological/ fossil/ecometric data to supplement climate and agricultural models could contribute to understanding the potential for anthropogenic refugia, for a more holistic conservation approach.

Fossil-data is a versatile and valuable component in the conservation tool-box. It contributes to conservation decisions about the state that a system should be conserved in, informing re-wilding efforts, making radical conservation-actions less-risky, informing natural-base-lines, identifying species and relationships vulnerable to environmental-changes, and understanding environmental-tipping-points. Coupled with ecometrics which provides functional-information for conservation and is especially relevant in the conservation efforts in novel-ecosystems, these paleontological methods are critical to effective and sustainable conservation action. Certain limitations exist such as the methods being less available for are species restricted to areas of low fossilisation potential. Nevertheless, the data has and will continue to be instrumental in global conservation-efforts.

What makes polar marine species amongst the most threatened by future climate change.

The polar regions are becoming ‘hot-spots’ of global-warming, with sea-surface temperatures having risen 1°C around the Western-Antarctic-Peninsula. Polar marine-species represent a unique community that has evolved in harsh ocean-environments; the nature of conditions varies between the Northern-and Southern sea-beds, yet both are characterised by cold-extremes resulting in similar adaptations. In many ways, it is the species’ adaptation to their environments which make them vulnerable to climate-change; especially their adaptation to relative stability. The increasingly isolated nature of Antarctica means that these species are even less-adapted to change compared to Arctic-species. Climate-change poses two main challenges for polar-marine organisms; temperature changes and ocean-acidification.

The responses are limited to genetic-evolution and phenotypic-plasticity as migration of native-species is not viable due to the relative-isolation and geographical-position. In this essay I suggest that the aspects making polar-marine species some of the most threatened by climate-change are mostly biological; their evolutionary-trajectory has resulted in poor-adaptive-capacities due to long-periods in a stable-environment. There has been no selection for traits which confer adaptability, thus in the face of environmental-change they are particularly vulnerable.

Here, I consider particular-adaptations in turn, demonstrating how each results in maladaptive-outcomes in the context of climate-change, these include: reproduction-metabolism-seasonality and cellular-responses. I also consider non-analogue environmental-changes as factors enhancing the threat. This discussion focusses-mainly on the Southern-sea-bed examples as adaptations and associated-vulnerabilities are more pronounced; many of these are applicable for Northern-polar-marine-species. Whilst both polar-regions contain species highly threatened by climate change, the threats themselves vary; in the Arctic the dominating threat is invasion and trophic cascades, whereas in Antarctica, the lack of adaptive-capacity to higher-temperatures threatens species more-significantly.

Ocean-acidification

Studies on the impacts of ocean-acidification on Antarctic-species is limited, however, it is indicated that there is a better-than-predicted response to lower-pH-conditions. Where long-term and multi-generational studies have been conducted, conclusions of progressive-adaptation and positive impacts of parental-acclimation have been found. In this respect, polar-marine-species are not considered highly-threatened. Nevertheless, the impacts of warming on both-biology and environment suggests a significantly reduced adaptive-capacity.

Reproduction|Development

The reproductive strategies of Antarctic marine species make them vulnerable to climate change due slow development and relatively few offspring; thus, reducing the potential rate for genetic-evolution. In Antarctica, large egg-size and reduced egg-numbers have been observed in a number of marine-species, including amphipod crustaceans and shrimps. Increasing data on fish also shows a trend from smaller, pelagic eggs at low latitudes to bigger, demersal eggs at higher latitudes(Leis-et-al-(2013). These trends are associated with the gradient in marine-productivity, and the energetic costs of egg production, previously-related to pelagic-changes in Thorson’s-rule, disproved with the advent of taxon-data. Nevertheless, Antarctic marine species tend to have fewer offspring and this pattern limits the rate at which they are able to evolve genetically. This feature makes them increasingly vulnerable to climactic-change.

In addition to long generation-times, increased temperatures threaten the dispersal potential of larvae because higher temperatures cause the larval-development-stage to be passed through more rapidly. The consequences of reduced-dispersal are species-specific due to varied development-strategies. In the example of Sterechinus neumayeri an increase in temperature from −2°Cto+0.5°C reduces the time from fertilisation to settlement from-120-to<90-days. These changes are substantial however, full elucidation of the impacts requires further investigation. It is nevertheless clear that changes in marine-temperature will impact dispersal and perhaps overall-distribution of certain species.

Cellular/Molecular

A number of cellular-adaptations which evolved to benefit marine-species in the extreme-cold of Antarctic-environments have been shown to negatively-impact the potential of species to acclimate in warmer-conditions. A prominent cellular-adaptation to cold environments is the increased lipid content in cell-membranes, an adaptation conferring membrane fluidity to maintain the structural/functional-integrity of membrane-proteins/ionic-transport at low temperatures. When warmed, these adaptations have negative-implications; one study finds that in two species of notothenioids, over a period of warming there is no plastic-response in the cell-membrane. Resoonse to warming in this way leads to failures including un-controlled membrane-fluidity with wide-ranging impacts on cellular functions such as ion. impacted. In this way, cellular-adaptations to cold limit the ability of marine-species to adapt to warming.

Enzyme functions showing adaptation to cold are thermally-limited in a similar way to membranes. To combat the high-oxygenation-levels, antioxidant enzymes are needed; optimization of these enzymes requires a a trade-off with their thermal-stability. Recent studies show that responses vary between species. One example where the mechanism is better elucidated is the species Aequiyoldia eightsii, in which a cytotoxic chemical O-propionyl-carnitine is produced as part of the antioxidant-inducing pathway. Whilst this adaptation confers protection against lipid peroxidation increasing temperatures cause this trait to become mal-adaptive (Sayed-Ahmed-et-al-(2001)).

A further example of cellular-level changes contributing to maladaptive-traits in climate-change conditions is the presence of step-wise genetic changes. The presence of step-changes has been facilitated by the prolonged-periods of stability, where there has been no fitness-cost to lacking plasticity or adaptive-capacity. A trait-example of this is the loss of globin-genes; due to high oxygen-levels in the water and low-metabolic demands for oxygen, the selective-pressure for erythrocytes is relaxed. Contemporaneously, erythrocytes/oxygen-carriers pose a disadvantage as they increase blood-viscosity, increasing energetic-costs for blood-transport. In 7/8 families of Nototheniodei, globin-genes have been reduced significantly. This step-change poses a challenge to thermal-adaptation as re-gaining genes requires longer time-scales than is permitted by current rates of ocean-warming. The lack of heat-shock response due to loss of chaperone-protein-expression is an additional stepped-change which limits the ability of species to respond to stress-factors, including thermal-challenges.

An additional molecular-adaptation to the cold is antifreeze-compounds, evolved from a pancreatic-trypsinogen-serine-protease-progenitor (structurally similar antifreeze-glycoproteins also found in Arctic-gadoids, arising from a conergent evolutionary-route). Biosynthesis of this compound is energetically-expensive, hence at higher temperatures will become maladaptive. Antarctic-Notothenioids synthesise antifreeze continuously; Arctic-fish exhibit seasonal patterns of antifreeze-biosynthesis. This is an efficient energy-saving strategy, that avoids costly biosynthesis when freezing is not a danger. These findings suggests that even a small increase in environmental temperatures will not pass unnoticed in biosynthesis control which is not viable in warmer conditions.

Resources/Seasonality

Climate change is predicted to impact the metabolic energy-costs of the overwinter-period in marine-systems. If the stored resources are insufficient, winter survival may be compromised. The majority of Antarctic-primary-consumers feed during the summer phytoplankton-bloom, which occurs for a short period annually. In response to the low-food-availability in winter, many Antarctic-species stop feeding and reduce metabolic-rates, sometimes to a hypometabolic-state, observed in molluscs, fish and starfish. This seasonality of primary-production is driven by light/nutrient availability, which is unlikely to change due to global-warming. Increased temperature also increases the rate at which digestive enzymes function, thus the rate at which food is processed; this leads to a scenario where marine-species are vulnerable to starvation during the winter due to increased metabolic costs in warmer waters.

Metabolism

Marine-polar species have limited tolerance of changes in water-oxygen content, making species vulnerable to thermal increases due to the impacts on oxygen%. This progressive loss in capacity for aerobic activity with temperature aligns with predictions from the oxygen-and-capacity-limited-thermal-tolerance(OCLTT) hypothesis (Figure 1). Clarke-et-al-(2017) suggest that there is no-uniform mechanism on which the upper thermal-tolerance is dependant. The temperature limits vary with the stage of the organism, and the most vulnerable stage is also species dependent. Studies also suggest that the time over which temperature change occurs impacts the response; although there is evidence of adaptation over time, it has also been shown that the accumulation of negative impacts caused by increased temperatures can decrease the ability of a species to adapt over time. These species-specific and complex results require further long-term-studies to elucidate the processes, but it is evident that OCLTT contributes to polar-marine-species’ sensitivity to climate-change.

Non-analogue environmental-change

Additional to biological-components contributing to the vulnerability of polar-marine-species, the nature of environmental-change in response to climate-change. This includes the secondary impacts of marine ice loss such as primary productivity timings as well as increased scour of the seabed due to collisions of ice-bergs. These complex interactions are not fully understood, evidence suggests that the polar-ecosystems are likely to be impacted by tipping points (Planetary-boundaries-Steffan-et-al-2009)causing un-predictable, rapid-change, with wide-ranging consequences for marine-species. The creation of models combined with robust-monitoring-systems will facilitate improved understanding of impacts in the long-term.

Having reviewed environmental and biological aspects which make polar-marine-species vulnerable to climate-change, it is clear that prolonged-stability has made species poorly suited to environmental-change. The capacity to adapt to warming-conditions is similar to that of tropical-species, where conditions are similarly-stable, however, tropical-species have the ability to migrate, and this is not a viable option for polar-marine-species. Furthermore, the period required to re-set their physiology following changes in temperature requires much-longer than tropical or temperate-species. This indicates that their ability to cope using phenotypic-plasticity is limited, compounded by long generation-times and fewer-eggs, reducing the ability to adapt-genetically. Anthropogenic influences, including the potential-dissolution of the Antarctic-Treaty, will contribute to threats in these regions, and should considered-parallel to biological/environmental-threats. Considering the uncertainty about future changes in the marine-environment, robust predictions of species responses are not yet possible; in this regard, there is a need for more long-term studies which incorporate transgenerational-effects in the context of ecosystems instead of isolated species. This knowledge is vital to inform future conservation-decisions.

Remedies and Reasons: What have been the major causes of decline in mangrove forests in recent years.

More than 35% of the world’s mangroves have already been significantly degraded, and with their continued degradation, there are negative consequences on ecosystem-services including the storage of carbon, fish production and coastal protection measures. Of the degraded sites, it is estimates that at least 6% have the potential to be restored, providing hope that some of the damage can be reversed. For the mangrove forests that remain intact, their protection requires an understanding of the threats faced at a local level in order to devise successful measures to protect them from future destruction. In this essay, I argue that there are four overarching threats faced by mangrove forests each with unique solutions, aligning with Jared Diamond’s evil quartet:

1) Overexploitation: Conversion for aquaculture and agriculture

2) Invasive species

3) Habitat destruction: Climate change and changing water conditions

4) Trophic cascades

Ultimately, I demonstrate that whilst the techniques for mangrove protection and restoration have already been established, the lack of success shows a need for understanding the weaknesses; I suggest here that whilst the theoretical techniques are sound, their implementation is flawed. In order for increased instances of success, integration of local knowledge and local involvement is essential.

1) Overexploitation: Conversion for aquaculture and agriculture

Overexploitation of mangrove systems has occurred as communities expand their agricultural and aquaculture activities, with estimates of its contribution to overall degradation at 60% (Rahman et al 2017). In certain areas of Malaysia, deforestation for palm oil/rice crops have led to >50% declines in mangrove cover. A further example of exploitation is the continued threat to mangroves from agricultural-expansion in Brazil. Around 70% of the mangroves are protected in preserved areas, making their management and monitoring much easier. An important aspect of the success in brazil has been the coupling of industries to create opportunity from mangroves; shrimp are a significant produce in brazil, and due to degrading water systems, there are growing issues with creating successful shrimp farms. The use of mangrove systems as natural water filtration and storage provides ideal conditions for shrimp farming. As such, local people have been able to monetize the natural services of the mangroves, without causing negative impacts. This method of valuation of ecological services has been increasingly utilised as part of conservation policy and management, linking two apparently disparate goals of promoting mangrove conservation and enhancing human well-being through innovative eco-farming methods.

2) Invasive species

As well as the direct anthropogenic impact of deforestation of mangroves, invasive species are a consistent threat to the integrity of mangrove forests. Spartina alterniflora is the most damaging invasive species in the mangrove wetlands of China. Concerns are amplified by the impacts of eutrophication from over-use of fertilisers on near-by agricultural land. These additional nutrients augment the ability of Spartina to suppress the growth of mangrove seedlings, resulting in changes to the competitive relationship between these two vegetation types. Action to prevent invasive species damage on the mangroves should be focussed on primarily stopping the spread of the invasive, and in areas already affected, removal is optimal. The difficult to navigate terrain of the mangroves makes these steps increasingly difficult, but effective where possible.

3) Habitat destruction: Climate change and changing water conditions

Habitat destruction is occurring through three avenues; habitat-fragmentation, increases in the frequency/intensity of extreme climactic-events and sea-level rises. Each of these presents unique conservation challenges.

Habitat fragmentation has been rarely considered as a largely influential threat on mangrove systems as pollinators are able to move freely across water unlike in terrestrial habitats, and propagules similarly are more extensively dispersed in the water. Harmansen et al (2017) studies the effects of fragmentation on mangrove recruitment, finding significant-evidence for negative impacts. Given these findings, it is most sensible to conserve the largest stands of mangroves possible. Fragmentation effects such as these have been included in policy infrastructure in the protected reserves in the Sabah regions of Borneo. The aim here is to maintain the structural integrity of mangrove forests to retain optimal recruitment opportunity.

Less directly, increasing natural-disaster frequency and intensity is a consequence of changing climate in line with global warming, damaging mangroves. This is a global-issue and the preventative measures therefore involve the global-community. An example of where extreme events are having increasingly negative impacts are the mangroves of South Florida, where persistent hurricanes are causing significant damage. There are studies suggesting that repeated hurricanes have turned previously dense mangrove habitat into mudflats which show minimal signs of regeneration of mangroves (Smith et al 2009). Climate change mitigation is the optimal solution to this issue, although not time-practical. In order to prepare for these circumstances, some have suggested technical solutions such as the creation of hurricane barriers in front of the mangroves in order to absorb some of the force. It is important to maintain awareness of solution-practicality; the majority of mangrove systems are in developing countries which may not have the resources to implement expensive remedial steps.

As well as increasing the intensity of extreme weather, climate change is affecting sea-level rise, with potentially negative impacts on mangrove health. Current projections for seal-level rise indicate there could be multiple types of effects on mangroves, but that these will vary depending on their geographical location (Ward et al 2016). Given that sea level rise will occur incrementally, it is hoped that mangrove systems will be able to move progressively inshore as this happens. Alternative intervention steps have been suggested including planting of mangroves further inland, which if conducted systematically with expert guidance provides a sound solution.

4) Trophic cascades

The threats to mangroves rarely occur in isolation, it is therefore vital to understand that any system is dealing with pressure from a number of threats at any one time. The combined effects are often synergistic such that the effects of multiple effects at once are greater than the sum of the isolated impacts. One example of this is the combined impact of eutrophication and altered freshwater-flows in Florida’s Everglades. This results in increased salinity in some locations with negative impacts on seedlings and increased competitive ability of other plants due to increased phosphorus and nitrogen. These effects combine to impact the seedlings and subsequent recruitment. When dealing with the combined effects, solutions are sometimes not as easy to implement as more effort and expense is required to ensure sustainable remedial action.

An overarching failure to the steps for halting and reversing declines as described above, including policy and on-the-ground planting methods, is the lack of communication and collaboration between scientists and the local community. Considering that the ecosystem-services provided by mangroves includes flood protection in excess of $82 million, investment in long-term solutions are in the interest of all stakeholders. One instance of where strategies have failed despite theoretically sound methods was in the Segara-Anakan-Conservation-and-Development-Project in Indonesia, which faces challenges from grassroots communities. The communities found that the scientists involved were more interested in actions which pleased the elite communities as opposed to problem solving solutions. This led to social opposition before the implementation of the project and little conservation action was achieved. This highlights the importance of incorporating local needs into the efforts. Transparency is essential to bridge the science-policy-community gap, as well as improved communication among between policy makers and all stakeholders through actions such as outreach and engagement.

As well as community engagement, increasing the technological and scientific methods in the arsenal of mangrove conservation will be invaluable steps towards creating policy and management solutions which are highly effective. Considering the vast areas of mangroves which are at risk of being degraded, prioritisation is a key aspect in the future planning of where to target remedial steps in mangrove systems. Instruments such as the Mangrove-Restoration-Potential-Map will become critical tools in the face of rising threats. These methods build on previous scientific efforts such as the Global Mangrove Watch, which used aerial data to build time series in order to assess the extent of damage. The new restoration maps have the potential to develop this in a more specific and pro-policy way, driving positive change. The restoration map method surpasses basic identification of vulnerable zones to include factors such as maximising carbon storage potential and positive fish nursery impacts. This integrated design is a key step in enabling increasingly data-driven policy and effective investment strategies as well as improving the confidence of governments and locals in the scientific method.

In conclusion, coastal mangrove systems provide irreplaceable services both to humans and nature, making their preservation critical for all stakeholders involved. Given the awareness of how important mangroves are in providing key ecosystem services, as well as numerous instances of both successful and failed attempts to reverse or prevent damage, it is clear that there is both motivation to change and the theoretical knowledge to make positive steps towards effective conservation. Nevertheless, the high failure rate in previous efforts highlights the need for additional steps to be made. Scientific contributions such as prioritisation maps alongside investment in community engagement will serve as these key steps in the improvement of mangrove conservation.