Tag Archives: galapagos

Chinese fishing vessels are plundering the waters near Galapagos

Nearly 300 Chinese vessels are pillaging the waters in the Galapagos Marine Reserve primarily for squid, which are essential to the diet of local Galapagos species such as hammerhead sharks, as well as for many commercial and recreational fish species, including tuna, according to an analysis by the NGO Oceana.

Credit Flickr Pedro Szekely

Using the Global Fishing Watch mapping tool, Oceana analyzed data from fishing vessels operating near the Galapagos Islands from July 13 to August 13. During this period, the NGO documented estimates the Chinese fleet logged more than 73,000 hours of apparent fishing. In fact, 99% of the visible fishing activity off the Galapagos during this period was by Chinese vessels

“For a month, the world watched and wondered what China’s enormous fishing fleet was doing off the Galapagos Islands, but now we know,” said Dr. Marla Valentine, Oceana’s illegal fishing and transparency analyst, in a statement. “This massive and ongoing fishing effort of China’s fleet threatens the Galapagos Islands, the rare species that only call it home and everyone that depends on it for food and livelihoods.”

The Galapagos Islands are a remote area nearly 900 kilometers off the coast of Ecuador and was once a “living laboratory” that inspired Charles Darwin’s theory of evolution. The area is an oasis for ocean wildlife with more than 20% of its marine species found nowhere else on Earth. The Galapagos Marine Reserve covers more than 133,000 square kilometers surrounding the Galapagos Islands.

There are more than 30 species of sharks living in Galapagos, some of which are threatened with extinction, such as the Endangered whale shark (Rhincodon typus) or the Critically Endangered hammerhead (Sphyrna lewini). Many of them constantly move between the islands and the mainland.

Credit Oceana

As part of its analysis, Oceana also documented Chinese vessels apparently disabling their public tracking devices, providing conflicting vessel identification information and engaging in potentially suspect transshipment practices, all of which can enable illicit activities. China has the largest fleet of distant-water vessels in the world, estimated at more than 17,000.

“The governments of the world must work together to ensure that all seafood is safe, legally caught, responsibly sourced and honestly labeled to protect the oceans and the people who depend upon them,” said Beth Lowell, Oceana’s deputy vice president for U.S. campaigns, in a statement

China is the leading nation when it comes to illegal, unreported and unregulated fishing, and its fleets have been routinely implicated in violations related to overfishing, targeting endangered shark species, illegal intrusion of jurisdiction, false licensing and catch documentation, and forced labor.

The high seas, also called international waters, cover 41% of the planet and 60% of all the oceans on Earth. However, there is almost no law that sets rules about how much, how, what and when to fish there. That’s why environmentalists are asking for a global treaty that sets a framework for conserving biodiversity in the high seas.

The waters around Galapagos are riddled with invasive species

Ships and vessels are bringing alien species to the Galapagos, posing threats to the pristine environment.

Image credits: Dustin Haney.

The thriving and rare environment on the Galapagos served as an inspiration to Charles Darwin as he was developing his groundbreaking theory of evolution. “Darwin’s Finches,” 12 species of finch on the island that have all evolved to specific niches, served as vital pieces of evidence to Darwin’s theory. But in addition to the finches, the iguanas, and all the endemic creatures, there are also a lot of invasive species in Galapagos.

As humans moved from one part of the world to the other, they brought many other creatures with them — sometimes willingly, sometimes without even realizing it. Regardless, these invasive species have had a massive impact on local fauna. The case of rabbits in Australia is infamous: the rabbits multiplied dramatically in a short period and overwhelmed the local ecosystem. Cats were brought in as predators (or for companionship), and they caused even more damage to the ecosystem. While other examples aren’t quite as dramatic as this one, invasive species have had a massive effect in almost all of Earth’s ecosystems.

Galapagos is no exception. Researchers have noticed for quite a while that invasive species have spread and adapted to the Galapagos, but this is the first study to quantify its extent. Lead author James Carlton from Williams College estimates that over 92% of invasive species were brought in by ships.

“Most of the introduced species treated here were likely brought to the Galápagos by ships,” the team writes in the study. “While we presume that most if not all of the many thousands of vessels arriving in the Galápagos Islands since the 1500s had marine animals and plants attached to their hulls, we hypothesize that the general absence in the Islands of extensive
shoreline structures (in the form of wharves, docks, pilings, and buoys) until the last half of the 20th century may have constrained extensive colonization by fouling species.”

 

The diversity of the invasion was remarkable. The team discovered over 50 introduced species, representing a 90% increase in the previous number known. These surveys were undertaken only around two of the larger islands, so the actual number of invasive species is almost certainly larger — potentially even two times larger, says Carlton.

All the discovered species were invertebrates, ranging from worms and mussels to crabs and moss. Yes, even something as inconspicuous as moss can have a severe impact on the local ecosystem. A simple moss called Amathia verticillata  has been shown to kill local seagrass and cause damage to fishing gears and commercial pipes.

The full extent of the damage has not been thoroughly assessed, but many of the discovered species have been found to cause substantial damage in other parts of the world.

The study has been published in Aquatic InvasionsDOI: 10.3391/ai.2019.14.1.01

 

Mermaids offer a rare view of our oceans’ subsurface

In this case, however, MERMAIDS are seismic sensors, deployed around the world’s oceans.

Floating seismometers dubbed MERMAIDs — Mobile Earthquake Recording in Marine Areas by Independent Divers — reveal that Galapagos volcanoes are fed by a mantle plume reaching 1,900 km deep. This photo shows one rising to the surface. Image credits: Yann Hello, University of Nice.

Most of what we know about the Earth’s inside comes from seismic studies. Just like a doctor analyzes your body using ultrasound, seismic stations can pick up waves from earthquake to image the interior of the planet or deduce some of its characteristics. The problem, however, is that most of our planet is covered in water — and we don’t have too many seismic stations in water.

“Imagine a radiologist forced to work with a CAT scanner that is missing two-thirds of its necessary sensors,” said Frederik Simons, a professor of geosciences at Princeton. “Two-thirds is the fraction of the Earth that is covered by oceans and therefore lacking seismic recording stations. Such is the situation faced by seismologists attempting to sharpen their images of the inside of our planet.”

With this in mind, Simons and Guust Nolet (now Professor of Geoscience and Geological Engineering) developed a new type of seismic sensor: a hydrophone. The hydrophone’s earthy cousin, the geophone, is routinely used in surveys to detect subsurface resource. Both types of sensors are essentially a very precise microphone, capable of picking up the sounds of distant earthquakes — or to be more technical, to pick up acoustic energy from earthquakes. The resulting hydrophone was fitted with a GPS and sensors for temperature and water salinity and was mounted on a platform called a MERMAID (Mobile Earthquake Recording in Marine Areas by Independent Divers).

MERMAIDs can dive down to depths as large as 3,000 m and are easily launched from even commercial or amateur vessels. They drift passively, usually at around 1,500 m deep, and whenever they detect an earthquake, they quickly rise to the surface to accurately gather GPS data and transmit data via satellite. They are currently the first marine instruments capable of transmitting seismic data in (almost) real time.

A bathymetric map of the Galápagos hotspot
region. Yellow dots show the location of MERMAIDs when the earthquakes were recorded. Image credits: Nolet et al.

The first fleet was launched in 2017 and now, an international team of researchers has presented the first scientific results.

For starters, MERMAIDs are useful to help scientists monitor abyssal currents — but that’s not even their main function. A more striking find is that the volcanoes on the Galápagos are fed by a so-called mantle plume: a magmatic source 1,200 miles (1,900 km) deep, connected to the surface volcanoes via a narrow conduit that is bringing hot rock to the surface.

These mantle plumes were first proposed in the 1970s as an important part of plate tectonics. Their existence has been confirmed in the meantime, but they have largely resisted attempts at seismic imaging because they are found in oceans, far away from seismic stations. The existence of this mantle plume was also indicated by abnormally high water temperatures.

In addition to filling in some missing puzzle pieces, the MERMAID network could also help geophysicists settle a long-lasting mystery about the Earth, which (thankfully) refuses to cool down.

“Since the 19th century, when Lord Kelvin predicted that Earth should cool to be a dead planet within a hundred million years, geophysicists have struggled with the mystery that the Earth has kept a fairly constant temperature over more than 4.5 billion years,” Nolet explained. “It could have done so only if some of the original heat from its accretion, and that created since by radioactive minerals, could stay locked inside the lower mantle. But most models of the Earth predict that the mantle should be convecting vigorously and releasing this heat much more quickly. These results of the Galápagos experiment point to an alternative explanation: the lower mantle may well resist convection, and instead only bring heat to the surface in the form of mantle plumes such as the ones creating Galápagos and Hawaii.”

The paper, “Imaging the Galápagos mantle plume with an unconventional application of floating seismometers,” by Nolet et al., has been published in Scientific Reports. doi: 10.1038/s41598-018-36835-w.

Different species can emerge in only two generations, new study reveals

A population of finches in the Galapagos has been caught in the act — the act being the creation of new species.

A member of the G. conirostris species, this bird flew from roughly 100 kilometers away to establish a new home on the Galapagos island of Daphne Major. There, the bird mated with a member of a different species to give rise to the Big Bird lineage. Credits: B. R. Grant.

Darwin cemented his theory of evolution in the Galapagos Islands, and indeed, few places on Earth showcase evolution so spectacularly. Researchers have continued to focus on the islands, with research sometimes yielding surprising results.

For instance, in 1981, Professors Rosemary and Peter Grant noticed the arrival of a male of a non-native species, the large cactus finch. The male mated with a local female finch, producing healthy, fertile offspring. Said offspring continued to mate, and so on. Now, 30 individuals, belonging to a new species, can be observed on the island.

Nothing too spectacular until now, although it is remarkable that researchers can study the development of a new species in isolation. What is spectacular, however, is how fast new species can emerge.

“The novelty of this study is that we can follow the emergence of new species in the wild,” said B. Rosemary Grant, a senior research biologist, emeritus, and a senior biologist in the Department of Ecology and Evolutionary Biology. “Through our work on Daphne Major, we were able to observe the pairing up of two birds from different species and then follow what happened to see how speciation occurred.”

In the current study, researchers from Uppsala University analyzed DNA collected from the birds and their subsequent offspring, learning that new species can emerge in as little as two generations. Keep in mind, this isn’t a new breed or a new subspecies, but a different species. They call it the Big Bird lineage.

It’s quite likely that new lineages such as this one have emerged many times, some successful, while others faded away. It’s unclear what the future will hold for the new generations of finches, but who knows — the might someday lead to completely different species.

“We have no indication about the long-term survival of the Big Bird lineage, but it has the potential to become a success, and it provides a beautiful example of one way in which speciation occurs,” said Andersson. “Charles Darwin would have been excited to read this paper.

The study has been published in Science.