Hawai‘i has been called the “extinction capital of the world.” But, with the exception of the islands’ birds, there has until now been no accurate assessment of the true level of this catastrophic loss. Invertebrates (insects, snails, spiders, etc.) constitute the vast majority of the species that make up Hawai‘i’s formerly spectacularly diverse and unique biota. A team of researchers, including scientists from the Pacific Biosciences Research Center (PBRC) at the University of Hawai‘i at Mānoa, the Bishop Museum in Honolulu, Howard University in Washington D.C., and the French National Museum of Natural History in Paris, recently published the first rigorous assessment of extinction of invertebrates in Hawai`i.

The team focused on the most diverse group of Hawaiian land snails, known as the family Amastridae, of which 325 species have been recognized – all known only from Hawai‘i. The researchers determined that only 15 of these species could still be found alive, and estimated that the rate of extinction may have been as high as 14 percent of the fauna per decade.

Native Hawaiian snail habitat on Pu‘u Kukui, Maui. Credit: Kenneth A. Hayes.

In a companion study published in the Proceedings of the National Academy of Sciences, members of the team, in collaboration with mathematics and bioinformatics specialists at the Pierre and Marie Curie University in Paris, addressed invertebrate extinction globally.

Since the 1980s, many biologists have concluded that the earth is in the midst of a massive biodiversity extinction crisis caused by human activities. Yet only around 800 of the planet’s 1.9 million known species are officially recorded as extinct by the International Union for the Conservation of Nature (IUCN) “Red List.”  Skeptics have therefore asked, “Is there really a crisis?”

“We showed, based on extrapolation from a random sample of land snail species from all over the world, and via two independent approaches, that we may already have lost 7 percent (130,000 extinctions) of all the animal species on Earth,” said Robert Cowie, research professor at PBRC and co-author of the two studies.

This loss far exceeds the number reported as extinct on the IUCN Red List. The IUCN’s number is based primarily on assessments of birds and mammals and essentially excludes invertebrates, even though invertebrates constitute roughly 99 percent of known biodiversity.

Based on their findings, the researchers show that the biodiversity crisis is real and stressed the need to include assessments of invertebrates in order to obtain a more realistic picture of the current situation, known widely as the “sixth mass extinction.”

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Régnier, C., Bouchet, P., Hayes, K. A., Yeung, N. W., Christensen, C. C., Chung, D. J. D., Fontaine, B. and Cowie, R. H. (2015). Extinction in a hyperdiverse endemic Hawaiian land snail family and implications for the underestimation of invertebrate extinction. Conservation Biology. doi: 10.1111/cobi.12565

Régnier, C., Achaz, G., Lambert, A., Cowie, R.H., Bouchet, P., and Fontaine, B. (2015).  Mass extinction in poorly known taxa. Proceedings of the National Academy of Sciences of the United States. doi: 10.1073/pnas.1502350112

For more information, visit: http://www.pbrc.hawaii.edu/

Starting this month, NOAA Ship Okeanos Explorer began two months of dives using unmanned remotely operated vehicles, or ROVs, to explore marine protected areas in the central Pacific Ocean. Anyone with an internet connection can virtually explore the deep sea with scientists and researchers from their computer or mobile device. Live streaming video is available during each and every dive.

“Given the unexplored nature of these areas, their remoteness and their known status as biodiversity hotspots, I’d be very surprised if we didn’t see many animals and phenomena that are new to science,” said expedition science team lead Christopher Kelley, associate professor of biology and program biologist at the Hawaiʻi Undersea Research Laboratory at the University of Hawaiʻi at Mānoa.

The ship and its crew will investigate deeper waters in and around Papahānaumokuākea Marine National Monument in the Northwestern Hawaiian Islands, Johnston Atoll in the Pacific Remote Islands Marine National Monument, and the Hawaiian Islands Humpback Whale National Marine Sanctuary.

Exploration Command Center on UH Mānoa campus

In the Hawaiʻi Institute of Geophysics Building at UH Mānoa, NOAA and UH Mānoa’s School of Ocean and Earth Science and Technology established an Exploration Command Center—a location where live video feeds from the ship and ROVs are displayed and scientists on land can communicate with the ship-board team, enabling tele-presence collaboration.

This is the first expedition of a major three-year effort to systematically collect information to support science and management needs within and around the U.S. marine national monuments and NOAA’s national marine sanctuaries in the Pacific.

Read more about the current expedition in the NOAA press release.

Thousands of feet below the ocean’s surface lies a hidden world of undiscovered species and unique seabed habitats—as well as a vast untapped store of natural resources including valuable metals and rare-earth minerals. Technology and infrastructure development worldwide is dramatically increasing demand for these resources, which are key components in everything from cars and modern buildings to computers and smartphones. This demand has catalyzed interest in mining huge areas of the deep-sea floor.

In a paper published this week in Science, oceanography professor Craig Smith from the University of Hawai‘i at Mānoa along with the Center for Ocean Solutions and co-authors from leading institutions around the world propose a strategy for balancing commercial extraction of deep-sea resources with protection of diverse seabed habitats. The paper is intended to inform upcoming discussions by the International Seabed Authority (ISA) and set the groundwork for future deep-sea environmental protection and mining regulations.

“Deep-sea areas targeted by mining claims frequently harbor high biodiversity and fragile habitats, and may have very slow rates of recovery from physical disturbance,” said Smith.

Smith led a team of scientists that helped the ISA design Marine Protected Areas (MPA) for the deep sea’s first regional environmental management plan in 2012. Located in an area of the Pacific Ocean known as the Clarion-Clipperton Zone (CCZ), the plan honored existing mining exploration claims while protecting delicate habitats by creating a network of MPAs. The CCZ serves as a model for how future deep-sea ecosystem management could unfold.

“Our purpose is to point out that the ISA has an important opportunity to create networks of no-mining Marine Protected Areas (MPAs) as part of the regulatory framework they are considering at their July meeting,” said Lisa Wedding, one of the papers’ authors and an early career science fellow at Stanford University.  “The establishment of regional MPA networks in the deep-sea would benefit both mining and biodiversity interests by providing more economic certainty and ecosystem sustainability.”

The ISA is charged with managing the seabed and its resources outside of national jurisdictions for the benefit of humankind.  According to the United Nations Convention on the Law of the Sea (UNCLOS), the deep seabed is legally a part of the “common heritage of mankind,” meaning that it belongs to each and every human on the planet.

“The ISA is the only body with the legal standing and responsibility to manage mining beyond national borders,” said Kristina Gjerde, an international high-seas lawyer and co-author on the Science paper.

Since 2001, the ISA has granted 26 mining exploration contracts covering more than one million square kilometers of seabed, with 18 of these contracts granted in the last four years.  As part of strategic environmental plans to protect deep-seabed habitats and manage mining impacts, researchers recommend that the ISA take a precautionary approach and set up networks of MPAs before additional large claim areas are granted for deep seabed mining.

“Given our paltry understanding of deep-sea environments, regional networks of MPAs that designate significant portions of the deep seabed as off-limits to mining would provide key insurance against unanticipated environmental impacts,” said co-author Steven Gaines, dean of the Bren School of Environmental Science & Management at the University of California, Santa Barbara.

Mining impacts could affect important environmental benefits that the deep sea provides to human beings. For example, the deep-sea is a key player in our planet’s carbon cycle, capturing a substantial amount of human-emitted carbon which impacts both weather and climate. Mining activities could disturb these deep-sea carbon sinks, releasing excess carbon back into the atmosphere.  The deep sea also sustains economically important fisheries and harbors microorganisms known as extremophiles, which have proven valuable in a number of pharmaceutical, medical, and industrial applications.

“This kind of precautionary approach achieves a balance of economic interests and conservation benefits,” said Sarah Reiter, a co-author from the Monterey Bay Aquarium’s Science and Conservation Program.

The upcoming ISA session on July 15 represents a critical juncture for defining the future of deep-sea mining and protection.

“The time is now to protect this important part of the planet for current and future generations,” said Larry Crowder, a co-author and science director for the Center for Ocean Solutions at Stanford University. “Decisions that affect us all will be made by the ISA this summer.”

New research, published today in eLife from a researcher at the Pacific Biosciences Research Center (PBRC), a newly integrated research unit of the School of Ocean and Earth Science and Technology (SOEST) at the University of Hawaiʻi at Mānoa, identified the neural circuit in the brain of the fruitfly (Drosophila melanogaster) that is responsible for detecting a taste pheromone, which controls the decision of male flies to mate with females.

In the natural world, sense of taste controls many behavioral decisions. For many animals, pheromones, which are chemical signals used for communication, influence the choice to mate. However, very little is known about how taste pheromones are processed in the brain.

The recent work by Joanne Yew, assistant researcher at PBRC, and colleagues explicitly tracked this process—identifying the taste cells on the fruitfly’s legs which detect the pheromone, locating the neurons in the brain which respond to the pheromone and mapping the connection between the two populations of cells.

The pheromone, named CH503, is produced by males, passed to females during mating, and stops other males from mating with the female – it is an anti-aphrodisiac for other males.

Many taste cells are found on the forelegs of flies, so Yew and colleagues used genetic manipulation to turn off activity in individual classes of these taste cells. They then tested whether males could still respond to the pheromone. Using this strategy, they were able to identify one class of taste receptors, called Gr68a, that is responsible for detecting the pheromone.

“Normally, males are repulsed by females that have been perfumed with the pheromone. However, when activity in Gr68a neurons is turned off, males will actively try to mate with females perfumed with the pheromone,” said Yew.

Next, the researchers turned off activity in different groups of cells in the central brain to determine whether males could still respond to the pheromone. One group of cells which produces the chemical Tachykinin appeared to be essential for detecting the pheromone.

Finally, the scientists established that the Gr68a neurons in the leg connect with the Tachykinin neurons in the brain. To do this, they introduced two sensors into the Gr68a and Tachykinin neuron populations. The sensors light up when neurons in the region are close enough to form connections. The researchers were able to detect connectivity between the two populations of neurons.

“This work identifies a molecular signal, Tachykinin, that controls the perception of taste pheromones and provides an anatomical map of where this information is processed in the brain,” said Yew. “By understanding the cellular basis of how taste information is encoded, we will be able to study how sensory signals shape programmed behaviors and influence complex social decisions such as the choice to mate. Potentially, we could devise a way to manipulate Tachykinin in pest populations to control reproduction.”

In the future, Yew and colleagues intend to further map the connections of Tachykinin neurons and examine how physiological state (e.g., hunger, stress) can influence the choice to mate via the Tachykinin pathway.

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Shruti Shankar, Jia Yi Chua, Kah Junn Tan, Meredith EK Calvert, Ruifen Weng, Wan Chin Ng, Kenji Mori, Joanne Y Yew (2015). The neuropeptide tachykinin is essential for pheromone detection in a gustatory neural circuit, eLIFE. doi: 10.7554/eLife.06914