Publication Date:
2021-03-29
Description:
In Central Amazonia, large mammals create water-filled puddles when consuming soil. These mineral licks
are visited by pregnant and lactating frugivorous bats; possibly for two reasons. Frugivorous bats could supplement
their mineral-depleted fruit diet by drinking salty water, or they could buffer dietary plant secondary compounds by
consuming soil. We analysed bat fruits from Ecuador and showed that they are depleted in elemental concentrations
(Na, K, P) compared with similar fruits collected from Costa Rica, where no mineral licks occur (n = 32). Analyses
of water from Ecuador revealed that water samples from six mineral licks contained more physiologically relevant
elements (Na, K, Mg, Ca) than four samples from river and stream water control sites (Mann–Whitney U-test). In
support of the nutrient supplement hypothesis, we observed bats drinkingmineral-enriched water at these licks (video
observation). Furthermore, blood collected from 68 bats differed in compositionwith respect to physiologically relevant
minerals (Na, K, Mg, Fe) from that of frugivorous bats captured at control sites. To test whether frugivorous bats also
consumed clay for detoxification, we checked for soil tracer elements in 31 faecal samples. Soil tracers are insoluble
in water and, thus, are not included in a strict fruit diet. Bats from mineral licks showed higher aluminium soil tracer
concentrations in their faeces than bat species that never visit licks, suggesting that frugivorous bats take up clay
material at mineral licks. Our results provide evidence that frugivorous bats ingest soluble mineral nutrients and
insoluble soil by consuming soil-enriched water at mineral licks, thus supporting the hypothesis that frugivorous bats
of western Amazonia may derive a dual benefit from drinking water from mineral licks.
Keywords:
detoxification; geophagy; nutrient supplementation; secondary metabolites; soil tracer
;
551
Language:
English
Type:
article
,
publishedVersion
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