Diet composition of Korean water deer (Hydropotes inermis argyropus) from the Han River Estuary Wetland in Korea using fecal DNA

Abstract

To investigate the foraging preferences of the Korean water deer (Hydropotes inermis argyropus) from the Janghang wetlands located in Han River estuary in South Korea, we elucidated their diet compositions using DNA extracted from their fecal samples. Samples were collected from the Janghang wetlands from June 2013 to January 2015. For dietary analysis, we amplified the internal transcribed spacer 2 (ITS2) and the large subunit of ribulose-1,5-bisphosphate carboxylase (rbcL) regions, followed by cloning and sequencing. We were able to detect 20 families and 35 genera of plants from 77 fecal samples, showing that water deer in the Janghang wetlands mainly preferred Salicaceae (27.5%), Fabaceae (17.5%), and Poaceae (14.2%). In winter, the relative frequency of woody plant detection (81.3%) was much higher than that in other seasons. Our results suggest that Korean water deer in Janghang wetlands browse or graze depending on the locally-available plants species in their habitat as intermediate feeders. Non-invasive approaches using fecal samples could be applied to study food webs of various species and ecosystems for conservation and management of wildlife.

Using high-throughput sequencing to investigate the dietary composition of the Korean water deer (Hydropotes inermis argyropus): a spatiotemporal comparison

“…6 and S6 ). This was also in line with a previous investigation conducted in the Janghang wetland in Korea, by which the increased proportion of woody plants in winter (80%) than in summer (28%) was reported 12 . The increased proportion of woody plants in winter has also been reported in the Chinese water deer 9 .…”

“…Additionally, the deer is more likely to feed on barks or twigs of woody plants in winter season when fresh leaves are not available and increased consumption of woody plants in winter than in summer is observed 9 , 12 . Thus, habitat vegetation and seasonal differences may have influenced their dietary habits and types 10 , 12 .…”

“…Specifically, we collected fecal samples of the water deer in two seasons (summer and winter) in two distinctive habitats (lowland and forest) in Korea, from which DNA was extracted to sequence the internal transcription spacer 2 (ITS2) region of plants. So far, the diet of the water deer has been investigated by feeding sign observation in the field 9 , 25 , microhistological analysis of the feces 9 , and molecular analyses of the feces, such as polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) of the rbcL gene 26 and Sanger sequencing (after cloning) of the rbcL gene 10 , ITS2 and rbcL gene 12 . In this study, HTS was used to sequence the ITS2 region, which is a primary DNA barcode marker for plants 27 , 28 .…”

“…Analysis of the gut contents in the Korean water deer, which died of traffic accidents or natural causes, revealed that forbs were main diets (70%) 11 . Another study conducted in Janghang wetland reported that the Korean water deer fed on forbs (49%), woods (36%), and graminoids (15%) 12 . However, studies conducted in England reported that the captive water deer fed mainly on graminoids and exhibited intermediate characteristics which might be nutritionally suboptimal 13 .…”

“…However, studies conducted in England reported that the captive water deer fed mainly on graminoids and exhibited intermediate characteristics which might be nutritionally suboptimal 13 . Additionally, the deer is more likely to feed on barks or twigs of woody plants in winter season when fresh leaves are not available and increased consumption of woody plants in winter than in summer is observed 9 , 12 . Thus, habitat vegetation and seasonal differences may have influenced their dietary habits and types 10 , 12 .…”