Roads negatively affect wildlife populations globally, causing habitat fragmentation that can facilitate mortality by access to forest for poaching and wildlife collisions with vehicles. Primate habitats are vulnerable to fragmentation exposing them to anthropogenic threats. Endangered dusky langurs (Trachypithecus obscurus) in Malaysia are often found in urban areas and have been frequent victims of vehicle collisions. To mitigate the hazardous impact of a busy asphalt road on wild dusky langurs in Teluk Bahang, Penang, we built the first artificial road canopy bridge in Malaysia in February 2019 to assist arboreal wildlife to move between habitat fragments more safely. Four days after the bridge construction, the first long-tailed macaque (Macaca fascicularis) was recorded via a camera trap crossing the bridge, and plantain squirrels (Callosciurus notatus) and dusky langurs first crossed one and eight months later, respectively. The bridge was upgraded from a single-firehose rope to a double-rope in August 2020 to assess the effectiveness of the two designs. In total, 2128 animal crossings comprising three mammal species were recorded between March 2019 and May 2021. Plantain squirrels crossed the bridge most frequently with 2075 crossings, long-tailed macaques crossed 32 times, and dusky langurs 21 times. There was a significant difference in bridge use according to species between the two designs (Chi-Square, p < 0.001). Since the construction of the bridge, the rate of previously frequently reported primate roadkills near the bridge location has dropped to zero. This successful pilot project has spurred the efforts to implement more canopy bridges country-wide to support primate conservation efforts and better protect arboreal wildlife from the negative impacts of linear infrastructure.

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Anthocyanins are an important part of the human diet and the most commonly consumed plant secondary metabolites. They are potent antioxidants, and in several recent studies the ingestion of anthocyanins has been linked to positive health benefits for humans. Here, we not peer-reviewed) is the author/funder. All rights reserved. No reuse allowed without permission.The copyright holder for this preprint (which was . http://dx.doi.org/10.1101/099432 doi: bioRxiv preprint first posted online Jan. 11, 2017; ! 3! show that when given a choice between two alternative samples of cabbage to ingest, captive born orangutans (n = 6) voluntarily chose the sample that contained greater amounts of anthocyanin. This occurred when they had to decide between samples of red cabbage (Brassica oleracea var. capitata f. rubra) from the same plant (p<0.05), and samples from green cabbage (Brassica oleracea var. capitata) (p<0.01). This indicates that anthocyanin holds a reward value for these hominids. There was no difference in L*a*b* colour between ingested and discarded samples in red cabbage, but when the choice was between two green samples, the animals chose samples that were more green and yellow. There was also no difference in the amount of lightness (L*) between chosen and discarded samples of either plant. It is therefore unclear if the animals use leaf colour in decision-making. In addition to other macro nutrients provided by plants, anthocyanin is also chosen by these endangered apes.