Did You Know?
Heart is a real big fluker!

About Heart

“Heart,” who is also known as “Ginger,” is a very well known and popular whale in the Depoe Bay region. Heart is a female who is particularly famous for being a “tall fluker,” meaning that when she dives, she arches her tail fluke high in the air before it glides elegantly into the water (check out her fluke series in the right image). Heart was first documented as a calf in 2010, which means that she is 14 years old (as of 2024). At 14 years of age, we would expect for Heart to have had at least one, if not more, calves by now, as it is believed that gray whales reach sexual maturity at age 8 or 9. However, Heart has never been documented with a calf. Why?

While we cannot know for sure, we have a theory that it might be linked to her body length. Recent work in our lab has explored how growth of PCFG whales has changed over time. Using measurements of whales from our drone data, we  investigated how the asymptotic length (i.e. the final length reached once an individual stops growing) for the PCFG whales has changed since the 1980s. Shockingly, we found that starting in the year 2000 the asymptotic length of PCFG whales has declined at an average rate of 0.05–0.12 meters per year. Over time, this means that a whale born in 2020 is expected to reach an adult body length that is 13% shorter than a gray whale born prior to 2000. In Heart’s case specifically, when we last measured her length at 13 years old, she was 10.65 meters long. If she had been born prior to 2000, then she would be 12.04 meters long by now at the age of 13. That’s a whole 1.5 meters (or almost 5 feet) shorter! 

You might be wondering how Heart’s length links back to her ability to have a calf. It takes a lot of energy to be pregnant and support the fetus, so by being smaller, Heart may not be able to store and allocate enough energy towards reproduction. Many of the whales we commonly see are shorter than expected based on their age (including “Zorro”), so we are monitoring the number and frequency of calves in the PCFG to see how this decline in length may impact the population. 

Facts and Figures

How to Identify Heart:

Heart has mottled pigmentation and bright white, vertical scratch on her left side that makes her easy to identify
Heart's right side is no less distinctive, especially because of a boat propeller scar she has forward of her dorsal hump
Heart's Health History
We have a lot of body condition measurements for Heart, especially from 2020 onwards. The measurements of Heart in 2018 and 2019 are lower than those than in 2016 and 2017, which makes sense given that they were from June at the start of the feeding season versus in September and October, towards the end of the feeding season when Heart would have experienced a lot of weight gain. The trends for 2020, 2021 and 2022 are mostly what we would expect to see for a whale during the feeding season with an increase from start to end, though there are some dips in body condition that do occur.

We fly drones over whales and then measure how skinny or fat they are from the images we capture. We compare the body condition of whales using an index called the Body Area Index (BAI), which is like the Body Mass Index (BMI) used to compare the body condition of humans. Small BAI values mean the whale is skinnier and larger BAI values indicate the whale is fatter.