NASA satellites help plan future for Palau fish stocks

In an effort to ensure food security and sustainability for future generations, the Palau government has partnered with fishermen to establish sustainable aquaculture farms close to their shores. To protect the country's rich ecosystems, their planning uses data from NASA's satellites. Credit: Fabio SikseiFreshly caught fish is ready to be grilled on the grill. The view: A breathtaking beach with the cobalt blues Pacific Ocean as the background.This is not paradise. This is a common Sunday in Palau, Micronesia's archipelago nation."We would go the Rock Islands and spend a few nights there. Then we would go fishing," said Fabio Siksei (a Palau fisheries specialist) about growing up close to the country's famous Rock Islands Southern Lagoon. "Most Palauan children have almost the exact same experiences growing up."Palau is a tiny nation of around 20,000 people. They consume more wild fish per person than any other country. However, the population of rabbit fish and other staples in their cultural diet has been declining over recent years due to a variety of factors including changing ocean conditions and increasing food demand.Siksei, along with others, are working with international scientists in order to create sustainable aquaculture farms in oceans. This will help meet the nation's food needs and preserve traditions for future generations. NASA satellites are used in their projects to protect the nation's shorelines, coral reefs and pristine waters.Siksei stated that the decline in fish stocks was due to the fact that [our waters] were unable to produce enough fish to sustain the population. This was enough for fishermen to begin to think about management issues. We talked to fishermen about how to ensure that fish stocks are healthy and that resources are available. It was also important to ensure that culture thrives for future generations, as fish is an integral part of our lives.Palau, which has more than 300 islands and a landmass that is twice as large as Washington D.C.'s, is one of the most tiny countries in the world. The country is surrounded by beautiful ocean and coral reefs for a paradise for divers. Its economy is primarily dependent on tourism and fishing.Siksei stated that tourism is an important economic driver, but Palau's islands are under increasing pressure to support the hundreds of thousands who visit the country during normal, non-pandemic periods.Siksei, along with others from Palau, have worked for many years with scientists from The Nature Conservancy in managing the aquaculture sector. They also found the best locations on Palauan shores where they could build the marine aquaculture farms that would meet future food production requirements.Siksei stated that the idea is to breed fish and shellfish while not disrupting marine ecosystems or other aspects of the country’s economy, culture, and nature. The team will be focusing on giant clams and rabbit fish, which are two types of seafood that have been part of the national cultural history.Siksei stated that "we don't want people to stop fishing or stopping people doing what they normally do." We're trying find a way for them to continue to live and enjoy these natural resources.The Potential of Marine AquacultureThe government of Palau and the fishermen have teamed up over 30 years ago with scientists from the Nature Conservancy to create marine protected areas, improve fisheries management, and address other environmental and social needs.The collaboration began with conversations with aquaculture farmers, who wanted to better understand the ocean circulation, the optimal distance to farm from shore, and other parameters that could make aquaculture economically viable and sustainable for the country.The team is also integrating multiple layers of satellite data into maps that Palauans can use to evaluate their goals when setting up aquaculture farms. The team has also received support from NASA's Earth Science Applied Sciences Program. They are now creating interactive mapping tools Palauans will use to find areas that could be suited for sustainable aquaculture.Robert Jones, the global aquaculture program leader at The Nature Conservancy, stated that marine aquaculture is more sustainable than any other form of animal protein production. However, if done wrongly, farms located in the ocean can cause more damage to marine ecosystems. This project aims to prevent this problem.Jones stated that almost every country on the coast has an aquaculture development program. They all agree that we need to increase production to meet increasing demand for seafood and animal protein. Jones said that there aren't many people who know how to plan and place the proper industry to protect the environment while still achieving their development goals.Aquaculture can cause poor water quality close to Palau's shores if it is done in an inappropriate manner. This is especially true for fish farms as fish can also produce waste, which can muddy water and alter ocean conditions, preventing corals from surviving.Jones stated that fish in a cage will poop. "If coral is in close proximity to the plume from the fish pen, it can really harm [the coral's] ability of survival." This puts additional stress on coral already suffering from [stress] due to climate change."Fish farms seen from spaceJones's team combines several layers of satellite data to create maps that Palauans can use for setting up aquaculture farms. These maps include maps that determine the water clarity. This is important for giant clam farm, which require sunlight to penetrate water in order to survive.Jonathan MacKay, Marine Spatial Scientist at The Nature Conservancy and NOAA who is responsible for the data and mapping, said, "We can look around the area and determine where there might be a better chance that sunlight reaches the giant clams and help them produce their energy."These maps are created by MacKay using satellite data from NASA's Terra satellites. He also uses data on sea surface temperature from NASA's Making Earth System Data Records to Use in Research Environments Program.MacKay stated that part of the project also examines climate change and how it might impact sea surface temperatures. "We can look at the lagoon to see where the warm water is and determine if there's not enough ocean circulation. Water sitting still will cause it to warm up faster than the surrounding water.Satellite images are used to estimate the underwater depth of shallow parts of the ocean. This is one of the highlights of the mapping tool. The project team relies on data from Landsat 8. This joint mission of NASA, the U.S. Geological Survey, has been monitoring changes to the surface of the planet's surface since 1972 and has the longest continuous record.These maps include almost 30 layers that overlay important environmental data such as the locations of dugongs or other marine animals that are protected by Palauas as well as social data about World War II historical sites or scuba diving spots that play an important part in tourism.A Promising Tool to Address a Global ChallengeThese mapping products have already been shared with Palauans via an online map and interactive training modules. They focus on remote sensing and geographic information systems and other important topics to help establish new marine aquaculture farms.These courses, which are led by MacKay, and hosted by The Nature Conservancy’s conservation training website, are offered in partnership by the Palau Community College to students of various backgrounds, including the country's Environmental Quality Protection Board.Siksei Jones and MacKay are committed to helping Palauans continue to use the maps with the new data layers in future. It's an aspect that NASA values greatly, according to Maurice Estes who manages the NASA program that supports this project. Because it can offer a promising toolet for coastal communities around the world that rely on the ocean and fisheries as food supplies, Estes said.Estes stated that they have developed a new method of using Landsat data for estimating the bathymetry in low-lying areas. This project addresses the global problem of sustainable food supply.