Back to the Field: NOAA biologists return to Papahanaumokuakea to study and protect Hawaii wildlife
by NOAA Fisheries 25 Jul 2021 19:41 UTC
NOAA teams recently departed to study and protect Hawaiian monk seals and green sea turtles in the remote islands of Papahanaumokuakea Marine National Monument © NOAA Fisheries
A team of biologists from NOAA's Pacific Islands Fisheries Science Center is setting off for a field season in the remote islands of the Papahanaumokuakea Marine National Monument.
The team departed Honolulu on the M/V Kahana II July 10, and the ship will return August 6. However, most of the biologists will stay behind for a season of hard work collecting data on some of the iconic threatened and endangered species of Hawai?i—Hawaiian green sea turtles and Hawaiian monk seals.
The work of NOAA field biologists in the monument
The primary goal of this research cruise is to set up biological field camps at five sites within the monument:
1. Lalo (French Frigate Shoals)
2. Kamole (Laysan Island)
3. Kapou (Lisianski Island)
4. Manawai (Pearl and Hermes Reef)
5. Holaniku (Kure Atoll)
Setting up camp on these remote islands is a big undertaking—each camp needs tents and all of the food, fresh water, scientific equipment, and safety supplies that teams of three to seven biologists will need for their stay of over 2 months. The research cruise team will also conduct monk seal surveys at islands where they do not establish camps—Nihoa, Mokumanamana (Necker) and Kuaihelani (Midway Atoll).
Once camps are established, the real work begins. Hawaiian monk seal biologists at the five camps will survey the islands to get an accurate count of monk seals. They will also monitor moms and pups to track reproductive success and attach identification tags to seals' flippers to help track individuals through their lives. At two of the sites (Lalo and Pearl and Hermes Reef), the team will use an underwater device (sound trap) to record monk seal vocalizations and understand the noises they hear.
Marine turtle biologists will join a team of two who have been at Lalo since early spring. The turtle team will count and tag male turtles and nesting female turtles, monitor nest success, and collect samples from hatchling turtles.
In addition to collecting valuable data, the field teams also conduct life-saving interventions to rescue individual animals and help the recovery of these vulnerable species. Every year, the field team rescues animals trapped in the man-made infrastructure on Tern Island at Lalo and frees animals entangled in marine debris. Additionally, NOAA teams help more juvenile seals survive by moving them off beaches with heavy shark predation and sometimes scaring away adult males that attack juveniles. Some juvenile seals also struggle to get enough food. At the end of the field season, the team will assess and may bring severely malnourished juvenile seals to the Ke Kai Ola Hawaiian Monk Seal Hospital for rehabilitation.
Field work after a missed season
This year's research season will take on extra meaning as the team returns to the field camps that they were unable to survey themselves in 2020 for the first time in decades. It is vital to continue adding to the conservation value of these long-running data sets—47 years for sea turtles and 36 years for monk seals.
Some of the information the team couldn't collect in 2020 is lost forever. We will never know the number of monk seal pups that were born last year, so we can't estimate the survival rates of those pups to adulthood. Nor will we learn the number of sea turtles that came to nest at Lalo in 2020 or their nest success. These are incredibly important metrics since the entire population's primary nesting island was severely damaged by a hurricane in 2018.
But not all is lost! The strength of a long-term dataset is that it provides sufficient information to overcome a rare lapse in data. This season we will collect new data, such as the size of the populations at each site, the makeup of ages and sexes of seals, and the survival rates of seals born prior to 2020. Some research goals will be delayed by the gap year. For example, the turtle team was in the middle of a large 5-year effort to tag all nesting females on Tern Island—the first time this was being done—because females generally nest every four years. Now, they will likely have to start a new 5-year census to fulfill the needs of study.
In most ways, data collection this year will be like any other for the monk seal field teams. The teams conduct surveys, catch up on tagging and vaccinating seals, and rescue animals as usual. The only difference is that we've been away from the Northwestern Hawaiian Islands for an additional year. We may find that we need to identify and tag more animals with missing flipper tags. The monk seal teams will also pay special attention to rebuilding the photographic identification database—the key to identifying seals without a tag.
Turtle biologists on this cruise will be joining a field team that got an early start at Lalo, arriving before the turtles started nesting, making this the first time in the program's 48-year history that teams will have been present for the entire turtle nesting season. That means the team has already tagged and sampled individual males they would have otherwise missed, as they often migrate back to the main Hawaiian Islands before the researchers arrive on location. As of mid-June, the team at Lalo has already counted 266 males, indicating that there are about two reproducing females to each mating male!
Wishing the team a safe season
Even as the Covid pandemic seems to ebb in the United States, we reinitiate remote field work with the utmost caution. While we take great care during every field trip to the monument to ensure the safety of our field personnel and guard these isolated islands from invasive species, this year has been filled with extra precautions to protect our personnel from infectious viruses, including Covid.
Our teams started their season working and training remotely. We coordinated carefully with the ship to load gear with minimal outside contact. All ship-going personnel underwent strict quarantine and testing procedures before joining the cruise. The team is off to a great start, and we wish them a safe and productive season!