A protocol for the aerial survey of penguin colonies using UAVs

Penguins, and many other seabirds, often nest in the open in large colonies, and so are amenable to aerial survey. UAVs offer a flexible and inexpensive method of achieving this but, to date, few published examples are available. We present a protocol for acquiring aerial images of penguin colonies using UAVs and describe simple, open-source tools for processing these into counts. Our approach is demonstrated using a case study for a penguin colony in the Falkland Islands. We discuss the advantages and limitations of UAVs for penguin surveys and make recommendations for their wider application

Robust wavebuoys for the marginal ice zone: Experiences from a large persistent array in the Beaufort Sea

An array of novel directional wavebuoys was designed and deployed into the Beaufort Sea ice cover in March 2014, as part of the Office of Naval Research Marginal Ice Zone experiment. The buoys were designed to drift with the ice throughout the year and monitor the expected breakup and retreat of the ice cover, forced by waves travelling into the ice from open water. Buoys were deployed from fast-and-light air-supported ice camps, based out of Sachs Harbour on Canada’s Banks Island, and drifted westwards with the sea ice over the course of spring, summer and autumn, as the ice melted, broke up and finally re-froze. The buoys transmitted heave, roll and pitch timeseries at 1 Hz sample frequency over the course of up to eight months, surviving both convergent ice dynamics and significant waves-in-ice events. Twelve of the 19 buoys survived until their batteries were finally exhausted during freeze-up in late October/November. Ice impact was found to have contaminated a significant proportion of the Kalman-filter-derived heave records, and these bad records were removed with reference to raw x/y/z accelerations. The quality of magnetometer-derived buoy headings at the very high magnetic field inclinations close to the magnetic pole was found to be generally acceptable, except in the case of four buoys which had probably suffered rough handling during transport to the ice. In general, these new buoys performed as expected, though vigilance as to the veracity of the output is required

Increasing accuracy: a new design and algorithm for automatically measuring weights, travel direction and radio frequency identification (RFID) of penguins.

A fully automated weighbridge using a new algorithm and mechanics integrated with a Radio Frequency Identification System is described. It is currently in use collecting data on Macaroni penguins (Eudyptes chrysolophus) at Bird Island, South Georgia. The technology allows researchers to collect very large, highly accurate datasets of both penguin weight and direction of their travel into or out of a breeding colony, providing important contributory information to help understand penguin breeding success, reproductive output and availability of prey. Reliable discrimination between single and multiple penguin crossings is demonstrated. Passive radio frequency tags implanted into penguins allow researchers to match weight and trip direction to individual birds. Low unit and operation costs, low maintenance needs, simple operator requirements and accurate time stamping of every record are all important features of this type of weighbridge, as is its proven ability to operate 24 hours a day throughout a breeding season, regardless of temperature or weather conditions. Users are able to define required levels of accuracy by adjusting filters and raw data are automatically recorded and stored allowing for a range of processing options. This paper presents the underlying principles, design specification and system description, provides evidence of the weighbridge’s accurate performance and demonstrates how its design is a significant improvement on existing system

Weight difference between the first approximation of penguin weight and the second approximation.

<p>Weight difference between the first approximation of penguin weight and the second approximation.</p

A flow diagram outlining how the weighbridge operates.

<p>A flow diagram outlining how the weighbridge operates.</p

A histogram of penguin weights calculated from weighbridge crossing data for 2011–2012.

<p>A summary of the data from the 2011–2012 breeding season is shown. The weighbridge recorded 71429 files. Data are shown for 31997 crossings in total with the penguin weight calculated from at least 1.5 s on the bridge—11141 outward crossings and 20856 inward crossings.</p

Photograph showing the weighbridge location.

<p>The terrain around the colony is such that there is only one route penguins can take both on their approach to the colony and on their return to the sea.</p

Dynamometer versus weighbridge weights.

<p>A comparison of weights calculated from weighbridge crossings with the mass of the same penguin obtained using a spring dynamometer once the penguin had crossed the bridge.</p