Monitoring MPAs

MPAs are one of the main approaches to protecting the ocean from the many threats it faces.

The process of designing MPAs, and deciding what human actions can occur where, should reduce or ideally stop some or all of these threats and enable biodiversity to stabilize or recover.

To determine the level of threat, and whether or not actions are working, MPAs should be monitored and compared to control sites (sites not in an MPA). Ideally, you should use an adaptive management approach, where monitoring influences improvements to future management and policy.

MPAs reduce local threats like overfishing and habitat degradation by restricting human activities within their borders. This has proven to be relatively successful where MPAs are adequately managed and resourced. However, MPAs have little influence on global and indirect threats like climate change and ocean acidification. Restricting activities at a local scale does nothing to stop the threat of climate change – though it could increase resilience to climate change.

So should we monitor things that tell us about threats we can’t control? Why monitor climate change impacts and acidification at a local level if there’s nothing we can do to mitigate them?

In a warming world we expect the distribution of marine species, most of which are highly sensitive to temperature, to move towards the poles. This means that, at a local scale, species that are at the warm end of their distribution could disappear from within an MPA. Similarly, acidification can affect many marine ecosystem processes. However, there may be less need to monitor these impacts than those we can directly abate (e.g., nutrient pollution or overfishing).

The key point is this: we need to be very clear about how monitoring helps meet the fundamental objectives of MPAs.

Why monitor?

We rarely do enough monitoring in conservation because our resources are limited. While every kind of monitoring (and research) has merit, this piece will focus on adaptive management monitoring in MPAs as this is the most useful for tracking progress towards outcomes for people and nature reasonably quickly at a local scale.

Monitoring MPAs can provide the following benefits:

Choosing what to monitor

There are hundreds of papers about MPA monitoring, and many, especially those in the academic literature, advocate a distressingly large number of indicators to monitor. Indicators include things like benthic cover of key species (e.g., coral, algae), fish biomass and water quality. Some suggest monitoring more than 50 indicators of an MPA and then combining them into complex amalgamated metrics. We do not recommend this for three reasons:

1. The more indicators you monitor, the more money it will cost both in data collection and analysis.

2. Because marine ecosystems are so complex, it’s tempting to reflect that complexity in what we monitor, but this involves setting many objectives, which confuses management and communication.

3. Some argue that we can create a single composite metric from the weighted sums of many metrics, but that means using many arbitrary weightings, and the final composite metric cannot be explained.

Bottom line: while it’s excellent that scientists are investing in the analysis of complex marine data sets, this is unnecessary for most, if not all, marine managers.

The most practical adaptive monitoring, designed to deliver on-the-ground conservation outcomes, is more likely to happen if we follow these six steps:

1. Determine your management information needs and what you need to know to track progress towards achieving the objectives of the MPA. For example, do you need to know about the status of an ecosystem service, the abundance of threatened or ecologically important species, or the spawning stock of a species that’s important for livelihoods in local communities?

2. Review the full range of monitoring actions available both in and outside the MPA. Consider the cost, feasibility and potential for success of each action.

3. Develop a theory of change that connects the monitoring actions with the indicators that you care about. These may be a direct measure, such as coral cover, or an indirect measure, such as nutrients that affect coral cover in the long term. The less direct the measure, the less certainty there is about how trends in the indicator relate to the things you care about.

4. Select the indicators to monitor based on the above steps, choosing indicators where changes are most likely to influence action on the ground to improve outcomes.

5. Monitor the indicators that you picked and analyse the data.

6. Change your management strategy accordingly, and advocate for important policy shifts by communicating results with decision-makers and stakeholders.

The objectives in the MPA's management plan are of fundamental importance in determining the management information needs. If the MPA's objectives are not clear or up-to-date, it’s hard to agree on management information needs as different stakeholders will have different views. That said, there are participatory and equitable processes for coming up with a reasonable suite of objectives (e.g., structured decision-making).

Setting objectives takes a long time but, from our experience, selecting indicators to monitor is often the hardest step.

We recommend choosing indicators that, if monitored, will deliver changed actions that cost-effectively improve outcomes, rather than selecting indicators based on what is commonly measured or interesting. Below are several questions you need to answer to pick the best indicators to monitor.

Climate change and monitoring

Monitoring the impact of climate change is rarely a priority because local actions can usually do little to abate the threat. In general, it’s far more important to monitor things that tell us about threats that we can stop, such as poaching or nutrients.

In turn, there’s evidence that managing these local threats can improve the resilience of marine ecosystems to climate change impacts. Some indicators, such as fish biomass and coral health, may tell us important things about the effectiveness of a given MPA in the face of environmental change, which may change priorities, design and management within the MPA under climate change in the adaptive management framework.

McDonald-Madden et al. (2009) provide some interesting examples of when conservation monitoring is, or is not, worthwhile in their paper “Monitoring does not always count”.

Limitations and gaps 

There are still many things we don’t understand about marine ecosystems, such as interactions between ecosystems and threats, and how certain indicators respond to different management actions. This is particularly true with the added uncertainties of climate change impacts and random events like cyclones.

A better understanding of conservation actions that improve generalized marine resilience to all threats would help prioritize management actions (see Module 4 Raja Ampat MPA Network case study).

Recent advances in technology (drones, remote sensing, etc.) should make some marine monitoring a lot faster and cheaper. This could shorten the evaluation and learning aspects of adaptive management, leading to faster responses and, ultimately, better conservation outcomes.