The whales of Chuckatuck, Part 1

Chuckatuck, Virginia is a small town in Isle of Wight County that sits near the James River. Over the years several quarries have been opened in or near the town, all of which exposed the Moore House Member of the Yorktown Formation. The Moore House is the youngest member of the Yorktown, and is late Pliocene in age (~ 3.5 million years). The Moore House is known for its abundant and diverse mollusk fauna, and nowhere is this displayed better than at Chuckatuck, which has an absolutely staggering number of shells. Mostly through the efforts of Buck Ward, VMNH has a collection of many thousands of shells from Chuckatuck, taking up more than a full case in the invertebrate collection storage room.

Whales have also been found at Chuckatuck, but they’re not common. More precisely, as far as I know there have been just two whale bones found there. The recent discussions on the blog about barnacles reminded me of these bones, and I decided to write a post about each of them.

One of the two bones is a large mysticete lumbar vertebra. Other than the fact that it comes from the Moore House, this wouldn’t normally be a very remarkable bone. However, this specimen is covered with barnacles:

In fact, my first count (I have to confirm it) turned up 643 barnacles. This is a big underestimate, though, because there are at least that many broken barnacle bases and scars that I didn’t count:

There are at least 28 barnacles or scars on this one tiny patch of bone:

Conservatively, I’d say there are indications that well over 1,000 barnacles colonized this bone. Even after death, whales can have a dramatic impact on the ecosystem.

Next time, I’ll look at the other whale bone from Chuckatuck.

This entry was posted in Chesapeake Group, Invertebrate Paleontology and tagged , . Bookmark the permalink.

6 Responses to The whales of Chuckatuck, Part 1

  1. Doug says:

    wow, that’s alot of barnacles! Are they fossil or modern?

    I know of at least two fossil whale falls: one from Italy and one from Ano Nuevo (island off the coast of California).

  2. Alton Dooley says:

    They’re fossil; this bone came from a quarry.

  3. boesse says:

    Hey guys,

    That’s pretty spectacular! That extremely dense encrustation is comparable to the sea lion bones I’m studying from Oregon – the three bones altogether share over 1400 barnacles (yes, I counted them all, as well).

    It will be interesting to see what the distribution of barnacles is like – are they all on one side? Are they absent only in certain spots where the bone rested on the seafloor? Or are they on all sides – indicating that the bone was periodically flipped over (or, conversely, flipped over once, and represents two colonizations)? Are all the barnacles of the same size? Are some encrusting others?

    …you can tell I’ve spent a bit of time thinking about the applications of barnacles to taphonomy.

  4. boesse says:

    Another thought – specimens like this are probably best not considered to be whale falls. Barnacles tend to indiscriminantly colonize certain (i.e. colonizable) substrates – if a clean bone occurs, it may get colonized along with terrigenous/intraformational clasts and invertebrate shells alike.

    Barnacles, IIRC, haven’t been recorded from many modern whale falls, likely because A) whale falls occur well below the influence of storm waves and fair weather waves and B) hard substrates are too rare in deep water environments where whale falls occur. Barnacles require relatively high energy environments in order not only to feed, but also to actually have a hard substrate to colonize (exposed hard substrates on the seafloor commonly only occur because of higher rates of erosion and nondeposition).

    In other words – most specimens I’ve ever seen with barnacles attached occur in shallow water, high energy environments of deposition and lack the typical whale fall fauna of opportunistic bivalves and gastropods, and instead are associated with shallow-marine hydraulically sorted shellbeds with typical shelf mollusk taxa; indeed, this specimen appears to be in a coquina or something similar.

  5. Alton Dooley says:

    The barnacles are all located on the posterior half of the vertebra; looks like it was sitting anterior face down, half-buried.

    Now that I’m looking, I’ve seen several more scars on bones in the VMNH collection; not huge numbers, but they’re around. Almost none still attached, though (even though we frequently find them attached to shells). I wonder if oil leaking out of the whale bones makes them slough off more easily.

  6. Doug says:

    I know Boesse. I haven’t commented in a while and wanted to sound like i had something relevant to say…

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