The Right Sentinel
Whales are the largest animals that live on our planet. However, they are fragile and are affected by human activities.
Southern right whales received their name from early whalers, who believed the species to be the “right whale” to hunt, as they generally swim slowly and float when dead. These whales were hunted in the 20th century to near extinction, causing a decline in global population size from about 100,000 whales to possibly fewer than 400 whales by 1920. Today, due to international protection from whaling since the1930’s, the species has recovered in some parts of its former range. Currently, large aggregations can be found in key winter calving areas, including South Africa, Australia, Argentina, Brazil and sub-Antarctic Aotearoa New Zealand. Nonetheless, despite the overall recovery of the species, the Chile-Peru and southeast Australia populations remain critically endangered.
In some of the key wintering areas, long-term photo-identification studies have been ongoing since the 1970´s, whereas genetic monitoring began in Aotearoa New Zealand in the 1990s. While methodologies for these long-term studies vary, most involve annual aerial surveys that count and photo-identify individual southern right whales in coastal waters. These studies have provided a wealth of information on behaviour, abundance and population trends over the past five decades, including a general population recovery post-whaling. However, in recent years, occurrence of whales on some of these coastal calving grounds started to fluctuate significantly, causing changes in population recovery rates and other measures For instance, in certain areas, females had calves, on average, ever three years but now it is every four years (or longer),,. Additionally, calf and adult mortality increased and/or body condition, an indicator of health, has decreased. As the species is still recovering from overexploitation, these changes are cause for concern, as they slow down population recovery.
How much food the whales can get determines how often they reproduce,, so a better understanding of southern right whale foraging ecology is critical. Therefore, this initiative will develop joint research projects to better understand how southern right whales use their foraging and calving grounds by employing a diverse set of tools, including geochemical markers, genetics, oceanographic modeling and satellite telemetry.
A greater understanding of the links between foraging ecology and population dynamics will provide insight into the recovery and persistence of southern right whales, now and into the future.
There are many obstacles and challenges to achieve five decades of uninterrupted whale studies: sustained funding over time, scientific training of human resources, political, social and economic ups and downs, modernizing scientific methods and updating technology, which today includes drones, satellite tracking, stable isotope analysis, studies of hormone levels, genetics, microbiome, body condition, nutrition, and many more. All these challenges can be overcome when the work for the study and protection of whales is done with passion, effort and perseverance. This is how we work from all over the world to study and protect southern right whales!
IWC-SORP Theme 6 “The right sentinel for climate change: linking foraging ground variability to population recovery in the SRW”.
https://iwc.int/scientific-research/sorp
This Theme aims to leverage the existing long-term datasets from key southern right whale wintering grounds, along with new knowledge on foraging areas and linkages between migratory habitats, to investigate the impact of past and future climate variation on the species’ recovery. It is a multi-ocean, multi-national collaborative project that utilises southern right whale annual photo-identification, genetic monitoring and sighting data from five countries (Argentina, Brazil, South Africa, Australia and New Zealand) across three continents. This IWC-SORP project lies at the basis of the formation of this Consortium.