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Getting a penguins-eye view of the ocean is now a reality. An international team of researchers have developed PenguCams, an new animal-borne camera system that can help track how much prey they need to eat, where they are finding fish, and how much energy they spend getting to their meals. The unique findingsand foragingare described in a study published January 28 in the journal PeerJ.Animal-borne cameras like the new PenguCams and National Geographics Crittercam can give researchers a view of behaviors they normally could not see. One of those important behaviors is how they interact with their prey. This is typically done by sampling their feces or what is inside the stomachs of dead birds, but this new method will help scientists understand just how much work it is for these penguins to get food. Understanding how an animal hunts and how much prey they need can help understand why they may be foraging for certain prey in certain spots.In the study, an international team of researchers affixed small, lightweight cameras to Humboldt, Tawaki, and King penguins in New Zealand. They then used the known distance between the penguins beak and the camera to determine a correction factora number that adjusts an observed value. The correction factor that the team created is a way to convert the pixel-based measurements in the footage into actual dimensions. It allows scientists to take a still image just before prey is consumed and measure how long or tall it is in pixels. Then, that pixel measurement can be converted into a real-world measurement in millimeters. This allows scientists to estimate just how much energy the penguin is getting from each foraging trip.The team tested video footage using a reference objecta grid with known dimensionsat multiple distances, water salinities, and angles. They then used these findings to create linear models that predict correction factors for distances that were beyond the tested range. This new correction factor takes into account distance traveled, refraction, and distortion to offer a practical tool to estimate size underwater.The study found that the correction factors were significantly different in air and water environments due to the differences in light refraction. However, these factors remain consistent across salt and fresh water, so they can be applied to several different marine habitats in the future.We created a new way to study marine predators through animal borne camera footage, Owen Dabkowski, a study co-author and student at the University of Otago in New Zealand, said in a statement. The correction factor allows measurements to be taken directly from video footage using a simple method. This innovative technique allows energetics of the prey to be calculated which can help explain the decisions made by predators during foraging.[ Related: When penguins divorce, the whole colony is impacted. ]The new method also takes distortion effects in the water and the air to ensure more precise measurements. The team also created a quick-reference table and have example footage demonstrating how the method works in real-world scenarios for other scientists to use.Using the correction factors developed with PenguCams could enable more accurate studies of ecological interactions. Having this data could better inform conservation measures for threatened or endangered species.PenguCams was developed by scientists from the University of Otago, the Tawaki Trust, the Global Penguin Society, the Antarctic Research Trust, and CONICET in Argentina.The post Finally, scientists get a penguins-eye-view of the world appeared first on Popular Science.