Conserving long-lived species: The importance of monitoring decades-old individuals
by NOAA Fisheries 17 May 18:26 BST
Southern Resident killer whales encountered during NOAA's PODs (Pacific Orcinus Distribution Survey) in October 2021 near the west end of the Strait of Juan de Fuca © NOAA Fisheries/Brad Hanson
Conservation and recovery of long-lived species requires continued monitoring of individuals. Meet some of the animals that have been known to scientists for decades.
Some marine species can live longer than 100 years. These long-lived, slow-growing species—including whales and sea turtles—can be indicators of the health of marine ecosystems. Their behavior can offer insights into environmental changes or stressors. Long-term research and monitoring of populations and known individuals is critical, especially for species that can live 100 years or more. Partnerships are critical to monitoring these species. In long-lived populations that are at risk, successful conservation requires detailed and consistent monitoring to track recovery progress.
Meet some of the individuals from endangered populations that NOAA scientists and our partners have been monitoring for decades.
Sequim: Southern Resident Killer Whale Matriarch
Endangered Southern Resident killer whales spend the summer and fall each year in Washington's Puget Sound, where scientists monitor individuals in three family pods ("J", "K," and "L"). Killer whale pods are led by the oldest females through tightly knit "matrilines," or groups of orcas descended from one grandmother or mother. Today, there are less than 80 individuals across the three pods due to historic and present-day human-caused challenges.
"Sequim," also known as K12, is the oldest female in the "K" pod at about 51 years old. She has given birth to five offspring, making her one of the most successful mothers in the population. Three of her calves and one of her three grand-calves are alive today. Sequim's matriline and the population as a whole have suffered high mortality. Continued monitoring of the three pods is critical to understand how the species population is changing over time. Research is also focusing on why many younger females are not producing as many calves as K12 has over her life. This information helps to inform actions that are important for the conservation and recovery of the Southern Resident population.
Pediddle (#1012): Nine North Atlantic Right Whale Calves and Counting
North Atlantic right whale mom Pediddle (#1012) is part of an exclusive club of right whale moms who have had nine or more calves! She was spotted in 1978 (making her at least 47 years old). She was seen with her first known calf in 1983 and with her most recent calf in 2023. Pediddle's oldest daughter, #1308, had four calves before she died in 2011 (due to a vessel strike). They include Snow Cone (presumed dead due to entanglement) and Chiminea (entangled twice), who each had calves of their own, making Pediddle a great-grandmother. None of Pediddle's other known calves had calves of their own, but her surviving granddaughters still may produce calves. As long as she stays healthy, Pediddle is likely to keep producing offspring as well.
Right whales can live into their eighties, or possibly even longer according to research on their counterparts in the Southern Hemisphere, the Southern right whale. Unfortunately, in the North Atlantic, right whales rarely live that long. Adults die primarily due to vessel strikes and entanglements in fishing gear, as with Pediddle's family. In recent years, changes to the ocean environment have redistributed their favorite prey, small fat-rich copepods, making the whales search farther for their food. North Atlantic right whales have become smaller, and take longer to produce calves as a result. Pediddle did not calve between 2009 and 2017, for example. Understanding where right whales feed, mate, reproduce, and migrate, is critical to reducing their risk of deaths and serious injuries. The North Atlantic Right Whale Road to Recovery describes NOAA Fisheries' efforts to address threats to the species and monitor recovery progress.
#1047: Hawaiian Green Sea Turtle Reproducing in Her Sixties
Sea turtles are one of the ocean's gardeners. Green sea turtles get their name from the seagrasses and algae they eat, which turns their fat green. The species faces several threats:
- Vessel strike
- Fishery bycatch
- Entanglement
- Loss of nesting habitat due to coastal development
- Environmental impacts, including hurricanes and sea level rise
Based on 52 years of research on nesting Hawaiian green sea turtles, we know they can live 70 years or more. They continue to reproduce well into their sixties. For example, NOAA Fisheries scientists tagged female turtle #1047 while nesting at Lalo (French Frigate Shoals) in 1975 when she was at least 20 years old. Researchers saw her resting on shore within these breeding grounds in 2019, making her more than 60 years old and still reproductively active. She has likely produced thousands of eggs in her lifetime, contributing to the overall recovery and conservation of the species. Long-term monitoring of sea turtle nesting trends is critical to track their threatened population status, trends, and recovery.
RH58 (Rocky): A Famous Hawaiian Monk Seal Mom
Hawaiian monk seals are only found in the Hawaiian archipelago, and are one of the most endangered seal species in the world. They live to be more than 30 years old and are mostly solitary, unlike other seals and sea lions. Human interactions, such as entanglement in fishing gear and toxoplasmosis, are some of their leading causes of death in the main Hawaiian Islands. Despite these threats, the species is showing signs of recovery due to our conservation and management efforts.
RH58, known also as "Rocky," rose to fame in 2017 when she gave birth on a busy beach in Waikiki during peak tourist season. Rocky was the first Hawaiian monk seal known to give birth there. She is an incredibly successful mother, giving birth to 15 confirmed pups throughout her lifetime. Rocky's first Waikiki pup, RJ58 (Kaimana), has since matured and successfully pupped two monk seals away from the spotlight. As for Rocky, in 2024, she gave birth on a different busy O'ahu beach, the Sand Island State Recreation Area, to a healthy male, RT58 ('Ili'ili). Matriarchs like Rocky are essential for the continued recovery of Hawaiian monk seal populations.