Whale News - October 2023
2023 season wrap up
I know that the 2023 season wasn’t what we were all hoping for. Unfortunately, days of staring endlessly out to sea waiting to see a glimpse of a whale is part of the reality of being a whale watcher (especially when watching for an endangered species like the Southern Right Whale). Being rewarded with privilege of seeing one of these magical giants makes it all worth it, and I am really grateful to the people who kept looking even though those rewards were few and far between this year (and the weather was awful a lot of the time).
This season there was only one cow-calf pair residing in Victoria and they did not stay long (approx. 3 weeks). It was a frustrating year for the monitoring team as well as we were unable to get any images from the drone to do a full assessment of the mother and calf’s condition. She proved to be too elusive and did not spend much time close to shore (which isn’t typical for a mother nursing a young calf).
What do the low numbers we observed this year mean? It’s not unusual to see calving numbers fluctuate from year to year in Southern Right Whale populations (given there can be several years between calves for individual females). Unfortunately, because the eastern population is so small, we do sometimes have years in Victoria where we only see one (or sometimes no) resident cow-calf pairs. However, over time if the population were increasing, we would expect to see less of these very low years which suggests something is limiting their recovery. Given that low numbers were seen in the western population this year as well, it is quite possible that food resources are having an impact on the population health. With changing climatic conditions, we would expect to see changes in distribution and abundance of prey which would have flow on effects to things like reproduction output and the overall health and growth of the population. Because our population remains small and our knowledge of what the whales are doing while they are not on our coast is limited, we have to look to other (better studied) populations to predict what might be occurring here.
For those of you who are interested in reading more about how Southern Right Whale populations around the world are being impacted by climate change here is an extract from our technical report that summaries some of the changes being noted in other populations. If you would like copies any of the papers cited here, please email me directly kasey.stamation@deeca.vic.gov.au and I will send them out to you.
…Concern over anthropogenic impacts on the recovery of populations of all three right whale species (North Atlantic Eubalaena glacialis, North Pacific Eubalaena japonica and Southern Eubalaena australis) is well documented (see Harcourt et al. 2019). Indirect impacts of climate change and habitat modification on health and reproduction are not well understood, but are predicted to have significant consequences for right whale populations (Leaper et al. 2006; Seyboth et al. 2016; Tulloch et al. 2019; Agrelo et al. 2021). A recent study at Península Valdés in Argentina found a marked increase in Southern Right Whale mortality rates following El Niño events (Agrelo et al. 2021). The authors hypothesised that the impact is greatest for females that need to replenish their energy stores following weaning of a calf. Lengthening of calving intervals observed in several right whale populations in recent years could be linked to food availability and changes in sea surface temperatures (Rolland et al. 2016; Charlton 2017; Brandão et al. 2018; Meyer-Gutbrod and Greene 2018; Vermeulen et al. 2018; Record et al. 2019). Myer-Gutbrod et al. (2021) demonstrated a direct link between birth rates of North Atlantic Right Whales and the abundance of a key copepod prey. North Atlantic Right Whales and Southern Right Whales are also becoming smaller (Stewart et al. 2021; Vermeulen et al. 2023). A recent study reported a 23% reduction in the maternal body condition of Southern Right Whales in South Africa over a 43-year monitoring period (Vermeulen et al. 2023). In Northern Atlantic Right Whales body length has been correlated to calf production and calving intervals (Stewart et al. 2022)…
It’s not all doom and gloom though for our eastern population of Southern Right Whales. Some positive news to come out of this season is that at least three cow-calf pairs were born in NSW this year and one in Tasmania. We look forward to next season and hope that we get to see some favourite whale faces and (maybe some new ones) return to raise their calves in Victoria’s waters in 2024.
Single Southern Right Whale photographed by Allen McCauley off Cape Nelson Lighthouse on 11/9/2023
Have your say…Please!!
Thank you to those people who have already completed the WhaleFace survey. We are keeping the survey open until October 31st so if you have a spare 10-15mins please fill in our questionnaire. We would like to make WhaleFace bigger and better in the coming years, with more education and engagement opportunities and some targeted survey programs for the community to get involved in. This does require resources though, so it is important for us to demonstrate that the community (and of course the whales) would benefit from these programs. Your questionnaire responses are one way for us to gauge the current benefits to the community and how you would like to see WhaleFace evolve into the future.
It is important that we continue to collect data on the eastern Southern Right Whale population to monitor their recovery and help with conservation efforts and planning decisions. Help us spread the word by being champions for WhaleFace - tell your friends and colleagues to join up to WhaleFace and/or Subscribe to our Whale News . Remember you can catch up on any past issues of Whale News by logging in and going to the Whale News tab.
Research Flights
Given the lack of whale sightings and uncertainty around funding for next year, we decided to hold off doing the final two surveys we had planned for the end of the season and instead carry over the funds to do two flights in the 2024 season. We will be looking for opportunities to secure funding for more systematic surveys (both aerial and land-based) in 2024 and will provide more details on what our 2024 monitoring program will look like, closer the commencement the next season. Fingers crossed we can continue to build on this important monitoring work!
We will be working through processing this year’s data (and previous data) over the coming months and we will be running some new analyses. We will be in touch with our latest findings as soon as we can.
A huge thank you to the Warrnambool community
This season we put a call out to the community to look for old photos (particularly between 1982-2002) to help us fill the gaps in the photo-id catalogue for Wilma. One of our regular WhaleFace contributors, Coralee Askew, jumped at the chance to help out with the search, and we are so grateful that she did! Coralee spent hours combing through old editions of The Standard on microfilm in the Warrnambool Library, visiting the Warrnambool and District Historical Society and talking to locals who had collected information and photos of whales in Warrnambool. So many people were willing to share their memories and stories about Wilma and other whales in Warrnambool. Some of the information we received came from personal dive logs and scrap books of newspaper clippings. In particular we thank Jean Britton, Kaye Whitehead, Janet MacDonald, Peter Ronald, Helen and Justine Ulmann, Peter and Lynn Goldstraw, staff at Flagstaff Hill and The Standard. Because of this community effort we are now able to confirm that Wilma did in fact have a calf in 1982 and we now have a photo for the catalogue for every year she visited Warrnambool.
Delving into the archives uncovered some more information about the life histories of some of our other regular females which could help us better understand this population and the recent trends we are seeing. We still have some work to do with this historical data, but we will share our findings with you as soon as we can. In the meantime, if you have images of Southern Right Whales in Victoria in the 80s and 90s please feel free to add them to WhaleFace or get in touch with me directly via email Kasey.stamation@deeca.vic.gov.au. These historical records are incredibly valuable in helping to uncover the mysteries of this endangered population.
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Below is one of Jean Britton’s poems that she wrote in 1982. Which paints a picture of whale watching in Warrnambool at that time (from the whale’s perspective), most still relevant today.
Background Photo taken by Coralee Askew
Hope to see you all out whale watching next year with noses red and chilly, and ears enclosed in caps!
Kasey
