Day gecko: why nectar colour matters more than taste, according to a study
Published by Planète Pets · managing editor: Clément Lacaille · how our guides are written
The giant day gecko of Madagascar does not live on insects alone in the wild: it also licks nectar from many flowers, acting as a pollinator for some local plants in the process. A study by Ingrid Minnaar, Angela Köhler, Cromwell Purchase and Susan Nicolson, published in 2013 in the journal Ethology, looked into what actually drives this nectar choice in the animal. Find our other pointers in the reptile food section.
Contents · 5 sections
Artificial nectars tested on several criteria
The researchers offered geckos artificial sugar solutions that varied in colour, colour saturation, contrast with their surroundings, and nicotine content — a bitter alkaloid used here as a stand-in for plant toxicity. The goal was to isolate which of these factors actually drove the animal's choice.
Colour wins out, the toxin only deters at high doses
The clear result: the presence of colour, and especially strong colour saturation, turned out to be decisive visual cues, far more so than the contrast between the nectar and its immediate surroundings. On the toxicity side, only a high nicotine concentration put the geckos off; at low concentration they did not avoid it, and sometimes even preferred it to a plain sugar solution with no alkaloid at all.
What the study does not show
The work covers a single species, Phelsuma grandis, tested under controlled conditions with artificial solutions rather than real floral nectar. It cannot be generalised to the whole Phelsuma genus, nor does it settle the species' tolerance to bitter compounds other than nicotine, nor the effects of repeated long-term exposure.
What this changes at feeding time
Commercial products mimicking day-gecko nectar, often vividly coloured, are therefore not simply a marketing gimmick: colour appears to play a genuine role in the animal's feeding response, consistent with what this study measured in Phelsuma grandis. That does not excuse skipping variety, particularly live insects for protein, a point covered in our article on transporting and handling the day gecko, a species that is otherwise fragile and deserves the same care at the food bowl as during capture.
Frequently asked questions
Can a day gecko live on nectar alone?
No, nectar remains an energy supplement in the wild as in captivity; insects stay essential for protein intake, particularly in growing juveniles.
Should brightly coloured commercial nectars be avoided?
No, nothing in this study supports that: the colouring instead appears to match a natural cue the species responds to, as long as the product is formulated specifically for day geckos. Find all our guides on the reptile hub.
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This guide is part of Planète Pets’s Reptiles universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.