Raptors and People

You may find this particular blog delving into grandiose explorations of they way in which I perceive the world; about the global impact of people, the way in which our ecosystems are being shaped, and the perceptions of and impact upon wildlife – so sorry about that.  But more importantly it should help explain why I lead myself into this particular research project – over and above my fascination and reverence of the Crowned Eagle in particular.

Anthropogenic environments:  Ecosystems which are created or modified to various extent by human modifications.  In the broadest view, it seems the entire biosphere as increasingly anthropogenic.  The changing atmosphere is the case in point.  While the change in atmospheric composition is still modest, rising carbon concentrations are already having a measurable influence, one which will continue to accelerate.  If runaway climate change forces humanity to implement one or several geo-engineering concepts it will be a stunning demonstration of the both the immense influence, and utter lack of control we have.

Anthropogenic modification is varied in scale and intensity of alteration.  Take for instance here a GoogleEarth view of Denmark, a landscape which is almost entirely composed of three basic categories: agricultural, silvicultural, or human domiciles. The urbanization of Copenhagen is seen stretching out from the eastern coastal margin.  All of the wildlife diversity that lives here does so because it is able to exist or exploit some part of this anthropocentric landscape.  There is a respectable diversity of birdlife, but Denmark is one of a handful of countries to have no nationally endemic bird species.

The island of Sealland of Denmark.

A particularly fortunate example of a species’ exploitation of a changed landscape is the response of New Zealand falcon to a particular timber plantation in the central North Island.  I assisted Dr. Richard Seaton during his PhD research on this falcon population.  A research project which discovered that in this ecosystem dominated by a monoculture of an exotic timber tree, here lives the highest density of NZ falcon known in the country.   Why should they thrive here when they are far rarer in native forests in the mountain ranges up and down the country?

Kaingaroa Forest is extensive – approximately 140,000Ha, and is sustainably harvested because it is divided into small compartments of uniform aged stands.  Because of this mosaic effect (despite the monospecies canopy) there is good structural variation, with plenty of edges between various age stands.  These edges allow understory plants to establish rapidly in growing stands.  They allow birds which require mature pine stands for shelter and nesting to be nearby clearfell areas with booming populations of detritivorous insects.  The birdlife is surprisingly rich, including an abundance of some NZ endemics struggling in native forests; whitehead, tomtit, and their parasites; long-tailed koel and shining cuckoo are particularly thriving.  Clearcuts attract loads of insects and grasses seed in these first years, which inturn supports the most abundant birds in the forest, introduced finches like chaffinch, greenfinch and redpoll abound.  And because of this abundance of birdlife, falcons can thrive, preferring to nest on the ground in clearcut areas.  But why does it seem that populations of rodents and their mammal predators have a greater impact in native forests than they do here?

Kaingaroa Timberlands from microlite. Copyright Richard Seaton.

The NZ falcon in particular has the potential to be very adaptable to various anthropogenic habitats.  But despite all the prey available in the agricultural and urbanized areas, why have they so far been unsuccessful urban colonizers?  The Falcon for Grapes project in the Marlborough wine region provided some explanations.  Despite promising signs that falcons have a significant impact of reducing grape damage by frugivorous birds, of over 21 falcons to have died during the course of the release project, less than 5% died of 'natural' causes.  Most troubling is that 47% of the birds (and 80% of females) were electrocuted, particularly at transformer boxes, feral cats and hedgehogs were responsible for several nest failures, others succumbed to collisions with windows or cars, yet others were shot by dove or chicken keepers, and a few died horrible deaths from various poisoning incidents, from bathing in sheep dip to falling into open diesel barrels. (Fox, N. 2010. in Wingspan Journal Vol 14)

While New Zealanders try to nurture and promote the remarkable and often unique wildlife, arising from a long pre-history of isolation in the absence of mammals, a contradiction that this is also the nation with the highest per capita cat ownership rate presents a jarring realization.   There is a disconnect between the way academics value biodiversity, and the way the majority of the public connects with nature (patting Tibbles on their lap while watching the telly).  If a falcon should turn up at a chicken coop or dove cot, it is all too often shot.  Even a surprising proportion of birders dread the appearance of ‘damn sparrowhawks’ at their garden bird-feeder. 

There are plenty of contradictions to be seen here.  I know of several ecologist in NZ which dedicate their career to conservation projects, and yet they keep cats at home - choosing to overlook the fact that these cats are eating geckos, wetas, and plenty of native birds caught in the garden.

Getting To The Point...

I treasure the ten weeks of fantastic travelling through South Africa last winter, and was overwhelmed by the incredible hospitality of the falconers, conservationists, and wildlife researchers who we spent time with.  The mid-point of the trip was marked by a week-long staying with a Kiwi friend doing a post-doc at the Fitztitute. 

There was a day in Cape Town that I cherish evermore.  We had been invited by Dr. Andrew Jenkins to accompany him for a day around Cape Town for some pre-season monitoring of Peregrine Falcons.  The story of the Cape Peregrines and their expansion into the urban environment is fascinating, particularly as each individual is colour banded and the population dynamics can be traced through the entire urbanizing expansion.  The first urban peregrine pair started breeding on a cooling stack of the refuse station, and after many years of decay this tower was planned for implosion. The city council sponsored installing alternative nest sites for the peregrines and Andrew put up the first boxes on nearby chimney stacks in 2005.  Within an hour of the demolition, with the smell of chordite in the air and dust still settling, the peregrines were copulating on their new nest box. This was the catalyst for urban colonization and boxes were put up at other sites where the peregrines could be better placed.  Another pair attempted to breeding behind an air-conditioning vent of the Rondebosch Childrens Hospital.  With the worry that these chicks would get cooked behind the vent, a nest box was attached to the building also, and these birds have remained here and have been extremely productive ever since.  They have produced four raucous chicks every year for the past seven years, all the while showering the hospital entrance with plucked pigeon feathers and whining and screaming as the juveniles develop. Now the hospital pair has children, and grandchildren, breeding in other areas of the city. 

The tolerance, and even reverence of these tenants by the hospital staff, and the infectious nature of their appreciation to many of the visiting patients and families is an example that ought to be emulated.  It demonstrates that the appreciation of nature is innate, but there are many biases in the way we view wildlife.  Most importantly, those biases can be shaped by a little information, or by the social context in which we share that appreciation of nature with others.

Rondebosch Childrens Hospital. The main entrance, peregrine nest boxes can be seen to left and right of the central brick facade.

A Cape Town urban peregrine, this one photographed at the Centuary City Apartments.

Dr. Jenkins gave me the first whiff of this project.  As we talked about Cape Town peregrines, touched on the success of urban Black Sparrowhawks, and various other urban exploiting raptors.  This was striking a chord with my underlying tendencies for research interests.  Andrew suggested I speak with Dr. Mark Brown at the University of KwaZulu-Natal when we got to Durban.

Having been invited to stay with Bruce Padbury in Hillcrest, we sure had an eventful few days.  Bruce had already organized for a UKZN Masters student to come and capture some Black Sparrowhawk fledglings for her study, which led me into climbing a lofty Blue Gum in at the Pietermaritzburg Police Station to install one of her nest cameras.  I did get to UKZN and bailed Mark up in his office, my eyes lit up when the topic of a study on peri-urban Crowned Eagles came up.  Sure enough, back in Hillcrest the next evening while we were wandering around the back section, a Crowned Eagle turned up, perching atop a nearby tree and, very purposefully looked down her(?) nose upon us.  This was the first wild CE I had seen.  Spectacular!

Hillcrest Crowned Eagle on the Keep

Close up with a great view of those hallux talons!

Some months later and I have developed a research plan, secured enrollment and study visa and today I sit, all packed and waiting to fly out to Pietermaritzburg tomorrow!