The ongoing news of nervous residents enduring cracking and crumbling tower blocks in Sydney and Melbourne came to mind when I reviewed a construction project in the Waterworks Reserve.
No problem of alleged inadequate design and poor building techniques here. Masters builders were at work, overseen by a master surveyor.
It might not be a tower block of concrete, glass and steel, but the welcome swallows applied the basic rules of construction all the same: a firm, solid foundation, carefully constructed and laid walls and a little bit of decoration here and there, not only to enhance appearance but to give a sense that this new-build merged with its immediate environment.
A construction built to withstands all the rigours of wild weather, all what Mother Nature could throw at it and in the scale of the five-month swallow mating season, a structure built to last.
A close look at a bird’s nest reveals intricate methods of construction. It might be mud used by swallows and martins, or the straw used by grey fantails, but attention to detail is always at the forefront.
Each year I study the construction of the swallows’ nest in a BBQ hut at the reserve, and each year it springs surprises. I wrote earlier in the season that the swallows always travel to the same patch of mud to select their building material. I deduced last season it was mudstone instead of the limestone or dolorite that form the other rocks underpinning the reserve. This was confirmed this season when the puddle the swallows usually use dried up and they went in search of another. They ignored puddles close to hand and travelled a little further to seek out a mudstone pool; clearly mudstone being the preferred building material.
In most bird species, it is usually the female who does most if not all the nest building, although with swallows the male and female share nest-building duties.
In species where the building role falls solidly on the males’ winged shoulders, females still keep a watchful eye on proceedings.
The role of the male in the building process can also form part of the vital paring and mating process. The male has to prove his strength, intelligence and ingenuity, the same qualities he has demonstrated with vibrant song and dance to attract a mate at the start of the breeding season.
Here the building-surveyor qualities of the female come to the fore, especially with complex construction. A case in point is the intricate, hanging nest of the masked weaver in Africa which takes special skill to build because it is suspended from trees above water.
The male can be made to build several nests until the female is satisfied with the construction. Some masked weavers have been known to build up to 12 nests before they can please their female. Twelve seems to be the optimum; beyond this the female simply flies off to find another mate with building skills that will ensure her home will not collapse around her.