Twitchers use Net to track shy bird

Scientists in the US have created a wireless sensor technology that will allow ornithologists to monitor the movements of the Leach’s Storm Petrel over the Internet.

For scientists studying the Leach’s Storm Petrel, monitoring the shy seabird’s nest activity usually meant having to stick a cumbersome remote camera into a burrow used for nesting.

But starting this week, biologists and ornithologists around the world will be able to monitor a popular breeding site in real time through the Internet while sitting at their computers.

Wireless sensor technology developed through a partnership between the University of California, Berkeley, and the Intel Research Berkeley laboratory is said to be making this powerful method of habitat monitoring possible.

Over the summer, researchers from the Intel lab, in the city of Berkeley, and from UC Berkeley teamed with biologists from the College of the Atlantic in Maine to install a network of more than 20 miniaturised sensors (motes) on Great Duck Island.

Each device, slightly bigger than the two AA batteries powering it, is now beaming back raw data about the conditions in the burrows and the island’s microclimate that will be viewable to the public at http://www.greatduckisland.net.

The motes are designed to detect light, barometric pressure, relative humidity and temperature conditions. An infrared heat sensor detects whether the nest is occupied by a seabird, and whether the bird has company.

Motes within the burrows and around the brush send readings out to a single gateway sensor above ground, which then relays collected information to a laptop computer locked away at a lighthouse on the on the 237-acre island. The laptop, also powered by photovoltaic cells, connects to the Internet via satellite.

The sensors used in this project are the newest generation of UC Berkeley motes, called Mica, and communicate with each other via radio signals sent at 40 kilobytes per second.

David Culler, computer science professor at UC Berkeley and director of the Intel Research Berkeley laboratory, worked with UC Berkeley graduate students to develop the sensor boards and networking software for the Mica motes.

‘The unique requirements of monitoring wildlife really pushed the engineering of the Mica motes in new directions,’ said Culler.

Biologists are not able to visit research sites more than a few times a year, and they avoid doing so to lessen the negative ecological impact of repeated human presence. It therefore became especially important to reduce the motes’ power consumption so the sensors would last between visits. The motes in the burrows can run continuously on two AA batteries for six months, while the relay sensor – which consumes more power – is rigged to a solar panel.

Biologists also have the flexibility of moving the sensors around to where they are needed most. ‘The network is self-organising,’ said Culler. ‘The nodes will automatically search for signals from neighbouring networks and adapt to changes in position.’

Alan Mainwaring, a research scientist at the Intel Research Berkeley laboratory pointed out that motes placed in an office building or home do not need to contend with rain, sand or a curious seabird’s beak. He said the motes in the burrows are protected from dirt and moisture by a 10-micron thick polymer coating that is biologically inert. An acrylic, cylindrical casing protects the motes above ground.

The raw information provided by the motes will help biologists understand why the Leach’s Storm Petrel favours Great Duck Island over thousands of other islands off the coast of Maine.