title: Temporal and spatial differentiation in microhabitat use: Implications for reproductive isolation and ecological niche specification.
abstract: Niche differentiation enables ecologically similar species to coexist by lessening competition over food and/or shelters and may be critical for reproductive isolation between closely related species in close proximity. Because no extra traits need to evolve, spatial and temporal differentiation may readily take place to complement other isolating mechanisms. Two closely related treefrog species occur together in Korea: the endangered Hyla suweonensis and the widespread Hyla japonica. Advertisement calls are differentiated, but it is unclear whether call difference is sufficient for reproductive isolation. We tracked individuals of both species to study fine-scale differentiation in microhabitat use in the diel cycle of the breeding season using a harmonic direction finder. tracking male movement patterns of both species revealed spatial and temporal differentiation in microhabitat use for calling and resting during the breeding season. Males of both H. suweonensis and H. japonica occurred in all 5 microhabitats identified in this study: rice paddy, ground, buried, grass and bush. Both treefrog species showed general similarities in calling from rice paddies and resting in grass and bush. However, H. suweonensis moved into rice paddies and produced advertisement calls 3 h earlier than H. japonica. These differences likely minimize contact between the species and provide an additional isolating mechanism. In addition, the activity of H. suweonensis may be contributing to the decline of this species, as resting in grass would increase dangers from predatory birds and habitat disturbance.
authors.affiliation: Department of Life Sciences and Division of EcoScience, Ewha Womans University, Seoul, Korea.|School of Biological Sciences, Seoul National University, Korea.
authors.forename: Amaël
authors.initials: A
authors.lastname: Borzée
authors.affiliation: Department of Life Sciences and Division of EcoScience, Ewha Womans University, Seoul, Korea.
authors.forename: Jun Young
authors.initials: JY
authors.lastname: Kim
authors.affiliation: Department of Life Sciences and Division of EcoScience, Ewha Womans University, Seoul, Korea.
authors.forename: Marina Andrade Martins
authors.initials: MA
authors.lastname: DA Cunha
authors.affiliation: Department of Life Sciences and Division of EcoScience, Ewha Womans University, Seoul, Korea.
authors.forename: Donggeun
authors.initials: D
authors.lastname: Lee
authors.affiliation: Department of Life Sciences and Division of EcoScience, Ewha Womans University, Seoul, Korea.
authors.forename: Eunchong
authors.initials: E
authors.lastname: Sin
authors.affiliation: Department of Life Sciences and Division of EcoScience, Ewha Womans University, Seoul, Korea.
authors.forename: Sunmin
authors.initials: S
authors.lastname: Oh
authors.affiliation: Department of Life Sciences and Division of EcoScience, Ewha Womans University, Seoul, Korea.
authors.forename: Yoonjung
authors.initials: Y
authors.lastname: Yi
authors.affiliation: Department of Life Sciences and Division of EcoScience, Ewha Womans University, Seoul, Korea. jangy@ewha.ac.kr.|Interdisciplinary Program of EcoCreative, Ewha Womans University, Seoul, Korea. jangy@ewha.ac.kr.
authors.forename: Yikweon
authors.initials: Y
authors.lastname: Jang
mesh_terms: D000818:Animals; D001001:Anura / Q000145:classification / Q000502:physiology*; D017753:Ecosystem; D008297:Male; D060047:Reproductive Isolation; D056910:Republic of Korea; D012726:Sexual Behavior, Animal; D013045:Species Specificity; D013997:Time Factors; D014828:Vocalization, Animal
keywords: harmonic direction finding; hylid treefrog; pre-mating isolation mechanisms; spatial isolation; temporal isolation