Learning about local species

 Having gotten no rain in wet New Zealand, it rained all morning here in the dry season of south Australia. The rain brought the kangaroos out from the shade and out into the open, which was fun. We spent a good part of this morning learning from Peggy Rismiller, who has been studying echidnas and tiger snakes on the Dudley Peninsula, the easternmost part of Kangaroo Island. This may seem like an odd combination, and really it is. Peggy laughed as she said that as tiger snakes bear live young and echidnas lay eggs, maybe they belong together. 

When she came to the island on a two-year research grant 35 years ago, there was a lot that was not known about the two species.  Her work has centered in Pelican Bay, which with its shallow water and reed beds serves as the “nursery” for baby fish that later populate the water off south Australia as adults. At some point early in the 20th century, some sheep farmers decided to put sheep onto the large islet in the bay. The sheep did not do well, but house mice were introduced to the island as a consequence. House mice out competed the native bush mice, and as house mice dig burrows rather than living on the surface, the local tiger snakes had to change their hunting methods. It is an example of rapid differentiation, as the tiger snakes on the islet now have much smaller heads, suitable for reaching into mouse burrows, than the same snake species on the main island. We haven’t seen a tiger snake yet, but we will keep looking (from a distance as they are very poisonous).

When Peggy started her echidna work, all that was known was that they lay eggs and breed in the winter. She developed the techniques to study their courtship, mating, egg laying, egg carrying (they do not incubate the eggs in a burrow), hatching, and nurturing the tiny puggles for eight months until they are weaned. She even had to develop the techniques to “unroll” an echidna to study it.  Echidnas have many interesting aspects beyond their reproductive habits. For example their spines are really hairs, deeply rooted and capable of being moved independently because the spine roots go into a layer of muscle below the skin. This is unlike a porcupine’s quills which are not deep rooted. We haven’t seen an echidna yet either, but we are hopeful.

Peggy is also one of the leaders in an effort to eliminate feral cats from the peninsula with a combination of technology and fences. Feral cats not only kill thousands of native birds each year, but carry diseases that threaten the sheep on local farms. If the peninsula project is a success, it could serve as a model for other selected areas, as all of Australia, New Zealand and the pacific islands suffer from feral cats. 

Later in the day we observed Glossy Black-Cockatoos, a rare local parrot, on a short nature walk. We also saw a second type of Black-Cockatoo (the Yellow-tailed) as we drove to our picnic lunch on Brown’s Beach, and enjoyed the scenery at the Cape Willoughby lighthouse. We finished the day with a wine tasting at a local organic winery. 

Pictured: Glossy Black-Cockatoo, Yellow-tailed Black-Cockatoo, Peggy with Flat Freda (the echidna model she takes to schools), Western Grey Kangaroos