That Soaring Seabird

Is there anything more beautiful than a soaring bird – kahu, karearea or our multiple seabirds.

I watched them avidly as a child over the hills and harbour of Wellington/Whanganui a tara.  One of my favourite poems was Gerard Manley Hopkins “The Windhover” -  “I caught this morning morning’s minion king-/dom of daylight’s dauphin, dapple-dawn-drawn Falcon, in his riding/Of the rolling underneath him steady air,…….”

Luckily for me my brother became an instructor at the Wellington gliding club and in my twenties his friend invited me out to the club and I learned that Hopkins had stumbled on a truth - air is gas and is often moving and sometimes that movement is steady.  Whole books have been written on the theory of flight but simply air can rise and fall depending on temperature and wind can make air do many strange things we can’t see with the naked eye; for example a strong wind hitting a land mass like mountains or an island can cause the air to rise in ascending waves.  It is these characteristics that allow some of our birds, particularly seabirds, to stop beating their wings and ride the air in soaring flight.   For over 100 years, humans, who for so long wanted to fly like birds, have mastered the technical aspects of building gliders and the skills to fly them.  Otto Lilienthal gets much of the credit for constructing practicable gliders.  He studied the way birds fly and based his craft upon the shape of their wings using cotton fabric over a framework of willow rods for his mainplane which he flew in 1896.

Many birds are perfectly designed for gliding with their hollow bones, aerodynamic shape.  Think of a tākapu/gannet, a superb soaring bird that we often see around Waiheke Island.  Like other soaring birds they use the position of their wings to deflect air downwards, which creates a force called ‘updraft’ that keeps them in the air.  However, birds like human glider pilots have learned about the value of ‘wind off cliffs’ (glider pilots call it ‘ridge lift’), and the hot air rising under cumulous clouds (thermals) and air waves caused by strong wind hitting landforms and rising beyond them higher and higher (wave lift).

One of my most memorable glider flights was above the Whanganui estuary in an open cockpit glider.  I was supposedly taking part in an Airwomen’s Association competition, all using the same type of glider, to try to land as close to a mark on an airfield but I was distracted because I realized that a flock of karoro/seagulls had joined me, gliding alongside me, close enough to touch.  Did they see me as a giant bird?  I will never know but I treasure that moment.

Sue Fitchett

Project Participant