Tracking the gray whales of the Pacific Coast Feeding Group
A PCFG gray whale surfaces off the Oregon coast, with the Yaquina Head Lighthouse in the background. Image credit: Craig Hayslip.

The gray whale population inhabiting the Eastern North Pacific, most recently estimated at about 20,000 animals (Stewart and Weller 2021), uses the warm waters of lagoons in Baja California, Mexico, during winter months for breeding and calving and then typically migrate to the Arctic to feed during summer months. However, the gray whales we call “summer residents” along the Oregon coast are part of a small population of around 230 (Calambokidis et al. 2020) known as the “Pacific Coast Feeding Group” (PCFG). These PCFG gray whales do not follow the rest of the population, instead ending their northbound migration in the Pacific Northwest to feed in shallow waters from northern California to Southeast Alaska (Carretta et al. 2021).

Between 2009 and 2013, we deployed satellite tags on 33 PCFG gray whales off central Oregon and northern California to track their movements over long periods of time (Mate 2013, Mate et al. 2014). The tags provided a wealth of new information about the movements of PCFG whales, including details about habitat use during the feeding season, which were published in Lagerquist et al. (2019). To further understand the movements of the tagged whales during their tracked periods, lab member Michaela Kratofil created the following five animations covering various temporal and spatial scales ranging from the full scale of the annual migration to the regional and local movements during the feeding season. These animations serve to better connect what we learned about PCFG gray whales from the tagging study with the information gained from ongoing studies being conducted by other researchers along their range.

Notice to mobile device viewers: the animations below are best viewed on a wide screen due to the panel layout. For best results we recommend viewing this page on a desktop computer.

Full migration, all tags animated over a common year

The combined tagging data from the three years (2009 in blue, 2012 in orange, and 2013 in green) shows how far some of these whales traveled, and also how many whales spend much of their time not too far from Hatfield Marine Science Center!

Although a handful of tags only lasted a few days or weeks, we were able to track tagged whales for an average of 119 days, and one tag lasted 383 days! The total distances traveled by these whales during the tracking period ranged from 42 to 7,222 miles. These long-duration tracks let us see the southbound migration to Mexico for 18 of the whales. We expected all of them to migrate to warm Baja California lagoons for the breeding/calving season, but one whale never migrated south and instead stayed in the Pacific Northwest for its entire tracking period (383 days)! While this whale never left the Pacific Northwest, it spent a lot of time roaming the coastal waters between northern California and Oregon.

Movements to Alaska

Although most of our tagged PCFG gray whales spent their time feeding along the coastline between northern California and northwest Washington, three whales traveled all the way to southeast Alaska (one in each of the three tagging years) and each whale’s tag lasted about 200 days!

Movements between Port Orford, Oregon, and Neah Bay, Washington

We’ve tagged some of the most well-known PCFG gray whales along the Pacific Northwest coast – these whales have been resighted over several years and even have their own names! In fact, one of the whales we tagged, “Orange Knuckles”, was first identified in 1999 and is featured on the IndividuWhale website by the GEMM Lab. Unfortunately, Orange Knuckles’ tag did not last very long for us to include in these animations, but you can learn more about this whale at IndividuWhale.

In this animation, we show the movements of some of these well-known gray whales while they were feeding from September through January of their deployment year. You can see how some whales jump between different feeding areas along the coast, while others tend to stay at one or two feeding areas.

Movements off central Oregon (Newport and surrounding area)

You may have noticed in the animation above that some of the tagged PCFG gray whales spend a lot of time close to Hatfield Marine Science Center. In this animation, we show some whales that were feeding in the Newport and surrounding area from September to November of their deployment year. You’ll see “Roadrunner” going off the map for a few days – this whale traveled north to a feeding hotspot off southern Washington (Grays Harbor) – and coming back to Newport before beginning its southward migration.

We also tagged “Coal” two times: first in 2009 and again in 2012. Although the tag did not last for long in either year, you can see how this whale spent its time in the same general area off Lincoln City in both years. At this scale, you can also see that some of these whales appear to move offshore for short periods of time. Given the nature of the Argos satellite system that we use to track the whales, not all locations are perfectly accurate – some of the offshore locations are likely unrealistic and the whale was more likely closer to shore.

PCFG gray whales get their own genetic test!

One of the main outstanding questions about PCFG gray whales is whether their population is genetically distinct and demographically independent from the larger Eastern North Pacific gray whale population, which could warrant separate management status (Weller et al. 2013). Toward this goal, for nine of the animals tagged in 2009 we also obtained a small skin sample using a biopsy dart for genetic analysis. In collaboration with the Cetacean Conservation and Genomics Lab (CCGL), we extracted the mitochondrial DNA (mtDNA) haplotype from these samples. A mtDNA haplotype is an identifying marker that is maternally inherited, so within a population, whales with the same haplotype are more closely related than those with different haplotypes. Combined with tagging data, we can refine the population distinctiveness question and also ask, for example, whether genetics reflect how different individuals move and where they spend most of their time.

This last animation shows the tracks of nine animals tagged and biopsy-sampled in 2009, this time colored by their haplotype. Among these whales are well-known individuals off the Oregon coast, including "Rat", "Boomerang", "Moby Dick", "Stamp", and "Harry". Of the nine animals, only two shared the same haplotype ("A"), while the other seven had a distinct haplotype. Immediately after tagging, the two whales with the same A haplotype (both male) appeared to feed in the same general area south of HMSC, with one ultimately migrating south to Baja California for the winter, where its tag deployment ended. The other whale (Rat) actually never migrated to the breeding lagoons, even though it was tracked for over a year. Gray whales never cease to surprise us!

Since we also obtained skin samples from the whales we tagged in 2012 and 2013, we have plans to expand the genetic analyses. It will be interesting to see how the mtDNA haplotype diversity and movement patterns are informed by the additional samples. Please check our separate PCFG DNA Register page for more information on this project!


This work was funded by the Office of Naval Research, the Pacific Fleet Commander of the U.S. Navy, the International Whaling Commission, the International Union for the Conservation of Nature, Exxon Neftgas, and private donors to the Marine Mammal Institute.


Calambokidis, J., J. Laake, and A. Perez. 2020. Updated analysis of abundance and population structure of seasonal gray whales in the Pacific Northwest, 1996-2017. Paper SC/A17/GW/05SC/68B/ASI01 presented to the International Whaling Commission Scientific Committee Annual Meeting, 12–24 May 2020, virtual. 73pp.

Carretta, J.V., E.M. Oleson, K.A. Forney, M.M. Muto, D.W. Weller, A.R. Lang, J. Baker, B. Hanson, A.J. Orr, J. Barlow, J.E. Moore, and R.L. Brownell Jr. 2021. U.S. Pacific Marine Mammal Stock Assessments: 2020, U.S. Department of Commerce, NOAA Technical Memorandum NMFS-SWFSC-646.

Lagerquist, B.A., D.M. Palacios, M.H. Winsor, L.M. Irvine, T.M. Follett, and B.R. Mate. 2019. Feeding home ranges of Pacific Coast Feeding Group gray whales. Journal of Wildlife Management 83(4):925-937.

Mate, B. 2013. Offshore Gray Whale Satellite Tagging in the Pacific Northwest. Prepared for Commander, U.S. Pacific Fleet, Pearl Harbor, Hawaii. Submitted to Naval Facilities Engineering Command Northwest (NAVFAC NW), Silverdale, WA 98315-1101, under Contract # N62470-10-D-3011, issued to HDR Inc., San Diego, California 92123. 18 June 2013.

Mate, B., L. Irvine, and T. Follett. 2014. Offshore Gray Whale Satellite Tagging in the Northwest Training Range Complex (NWTRC). Prepared for Commander, U.S. Pacific Fleet, Pearl Harbor, Hawaii. Submitted to Naval Facilities Engineering Command Northwest (NAVFAC NW), Silverdale, WA 98315-1101, under Contract # N62470-10-D-3011, issued to HDR Inc., San Diego, California 92123. June 2014.

Stewart, J.D. and D.W. Weller. 2021. Abundance of eastern North Pacific gray whales 2019/2020. U.S. Department of Commerce, NOAA Technical Memorandum NMFS-SWFSC-639.

Weller, D.W., S. Bettridge, R.L. Brownell Jr., J.L. Laake, J.E. Moore, P.E. Rosel, B.L. Taylor, and P.R. Wade. 2013. Report of the National Marine Fisheries Service Gray Whale Stock Identification Workshop. U.S. Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFSC-507.

For further information please contact lab PI Dr. Daniel Palacios.

Background image credit: Craig Hayslip