Canada geese - the downside of success

A gentle summer's evening and the tide was out - a long way.  There are extensive tidal flats along the coastline of the Abel Tasman National Park at the top of the South Island.  These intertidal areas are sandy, not muddy, so are great for walking and for bird watching.  The park is famous for the Coast Track which passes through original and regenerating forest along a beautiful coastline with interesting rock formations, golden sand and very clear water - and the tidal flats.  On the sand close to the southern park entrance, a group of Canada geese appeared to be doing a sedate dance...

These rather handsome birds were unflapped by the arrival of humans, no hiss honk or hassle - which is what I generally expect from geese.  As their name suggests, Canada geese (Branta canadensis) originated in North America.  They got to Europe without assistance but were deliberately introduced to New Zealand as game birds.  It's the usual story - there was population decline in their native range because of overhunting, habitat destruction and so on.  This was successfully countered with breeding programmes and conservation measures.  But Canada geese have been too successful in establishing in some new territories.  They are plant eaters and their impact on crops and pastures - damage, droppings, and the bacteria in their droppings - has made them a problem in some parts of New Zealand to the extent that in 2011 the government changed their status from protected.  They are "fair game".  They also tend to form large noisy groups with pestiferous confrontational behaviour.  But these ones maintained a dignified imperturbability.   

In the subdued light the golden colour of the sand is not very evident, but it can be seen in the shoreline rocks which will gradually erode to form the sand.  The black patterns on some of the rocks are clusters of little developing mussels. 

The rocks are of "Separation Point" granite - it tends to erode readily, creating the many interesting rock formations along the coast as well as the lovely sand.