PALAEO-ORNITHOLOGY IN BRITISH COLUMBIA
CHARLES HELM

The theory that birds evolved from theropod dinosaurs in the Middle Jurassic Period has become widely accepted. In a sense, therefore, visiting a theropod dinosaur trackway site is a type of palaeo-birding, such as through the Tumbler Ridge Museum’s guided tours to see theropod tracks near Tumbler Ridge.

However, BC’s Peace Region has many more specific palaeo-ornithological claims to fame. Because bird skeletons are so fragile and are infrequently preserved, tracks often provide the best means of learning about ancient birds. The first Mesozoic fossil bird tracks were described from Colorado in 1931 (Mehl, 1931; Lockley et al., 2009)). A report of Lower Cretaceous bird tracks from South Korea followed in 1969 (Kim, 1969). The third report in the global literature of Mesozoic bird tracks came from the Peace River Canyon (upstream from Hudson’s Hope) in 1981, with a report by Philip Currie of tracks from Aquatilavipes swiboldae,  a type of shorebird similar to a sandpiper (Currie, 1981). These have been inundated under the Peace Canyon Dam, but specimens were salvaged. The number and diversity of fossil avifauna known from North America remained relatively low, until further discoveries were made in the Tumbler Ridge area.

In 1994 a loose slab containing 100 million-year-old avian tracks was identified near the summit of Roman Mountain. The slab, weighing over 300 kg, was airlifted by helicopter to the Tumbler Ridge Museum in 2014, where, under optimal lighting, fifty tracks were discernible, and are now on exhibit. (Figure 1). A scientific paper may follow if these turn out to be previously undescribed tracks; however, they may possibly be ascribed to Aquatilavipes swiboldae .

Figure 1. Avian trackway, possibly of Aquatilavipes swiboldae, from Mt. Roman.

In contrast, tracks discovered in the Boulder Gardens hiking area were definitely distinct from anything that had been reported before. Paxavipes babcockensis— the Peace Region bird foot from Mt Babcock– became the second type of fossil bird track described from BC (McCrea et al., 2015). Containing tracks somewhat similar to those of modern plovers, the loose block was of Lower Cretaceous age, about 110 million years old. A theropod trackway and a single ornithopod track can be seen beside the 72 bird tracks on this slab, which is also on display in the Tumbler Ridge Museum (Figure 2). These tracks are preserved in convex hyporelief: they represent the infill layer of sand that filled in the tracks, rather than the original surface in which the tracks were made.

Figure 2. Multiple avian tracks from Mt. Babcock (Paxavipes babcockensis), along with two theropod tracks

Fossil bird tracks have subsequently been identified from three further localities in the Tumbler Ridge area. These have not yet been formally described, but one rock slab, discovered in 2014 and containing both theropod and avian tracks, is close to the Jurassic- Cretaceous boundary in age. These are therefore some of the oldest bird tracks in the world, and are on exhibit in the Tumbler Ridge Museum (Figure 3).

Figure 3. Replicas of two avian tracks (some of the oldest known in the world) from Tumbler Ridge from near the Jurassic-Cretaceous boundary.

To round out this suite of Peace Region fossil bird tracks, another track replica is on display in the Tumbler Ridge Museum (Figure 4). It features tracks of Limiavipes curriei, a crane-like species, on a surface that was exposed near Hudson’s Hope.

Figure 4. Limiavipes curriei track, made by a crane-like bird.

It is no accident that the track-makers are from families like sandpipers, plovers and cranes. Birds don’t leave tracks when they fly, or when they perch in trees or on cliffs, and their tracks are very unlikely to be preserved in forest and other vegetated settings. The avian track record thus comes largely from beach and dune and wetland palaeo-environments, where their footprints were recorded (alongside those of dinosaurs in the Jurassic and Cretaceous Periods, after which the dinosaurs disappeared).

A visit to the Tumbler Ridge Museum enables a rarity in birding: guaranteed sightings of the specimens on exhibit. The annual BCFO Conference was held in Tumbler Ridge in 2017, and palaeo-ornithology formed a prominent theme, including a lecture on the topic by Dr. Lisa Buckley.

Birds walked or ran on these surfaces, and left tracks that in near-miraculous fashion became preserved and have become re-exposed, for explorers and scientists to find and describe today.  Lovers of birds may be well served by not only enjoying watching them today, but also by sparing a thought for the birds of yesterday. Perhaps then we, as members of the Homo sapiens aviphilus tribe, may be better equipped to think about the birds of tomorrow and what influence we might have on their survival.

References

Buckley. L.G., McCrea, R.T., Lockley, M. 2011. Utility of multivariate analyses in ichnology: analyzing and resolving Cretaceous avian ichnotaxonomy. In: Xing, L., Lockley, M.G. (eds), Qijiang International dinosaur tracks symposium book of abstracts, Chonqing Municipality. Boulder Publishing.

Currie, P.J., 1981. Bird footprints from the Gething Formation (Aptian, Lower Cretaceous) of northeastern British Columbia, Canada. Journal of Vertebrate Paleontology, 1; 257–264.

Elbroch, M., 2001. Bird Tracks & Sign: a Guide to North American Species. Stackpole Books, Mechanicsburg, Pennsylvania.

Kim, B.K., 1969. A study of several sole marks in the Haman Formation. Journal of the Geological Society of Korea, 5: 243–258.

Lockley, M. G., Chin, K., Houck, K., Matsukawa, M. and Kukihara, R. 2009. New interpretations of Ignotornis, the first-reported Mesozoic avian footprints: implications for the ecology and behavior of an enigmatic Cretaceous bird. Cretaceous Research, 30: 1041-1061.

McCrea, R.T., Buckley, L.G., Currie, P.J., Plint, A.G., Helm, C.W., Haggart, J.W. 2014. A review of vertebrate track-bearing formations from the Mesozoic and earliest Cenozoic of western Canada with a description of a new theropod ichnospecies and reassignment of an avian ichnogenus. In Lockley, M.G. and S. Lucas (eds.), Tracking dinosaurs and other tetrapods in western North America. New Mexico Museum of Natural History Bulletin, 62: 5–94.

McCrea, R.t., Buckley, L.G., Plint, G., Lockley, M., Matthews, N.A., Noble, T.A., Xing, L., Krawetz, J.R. 2015. Vertebrate ichnites from the Boulder Creek Formation (Lower Cretaceous: Middle to? Upper Albian) of northeastern British Columbia, with a description of a new avian ichnotaxon, Paxavipes babcockensis ichnogen. et isp. nov. Cretaceous Research, 55: 1–18. DOI: 10.1016/j.cretres.2015.01.004

Mehl, M.G., 1931. New bird record from the Dakota Sandstone, of Colorado.
Geological Society of America Bulletin, 42: 331.