Ecology of Breeding White-Faced Ibis on Lower Klamath National Wildlife Refuge, California, Progress Report, 1995

Metadata Updated: December 11, 2019

The conservation and management of breeding Whitefaced Ibis (Plegadis chihi), a state and federally listed species of special management concern, requires comprehensive knowledge of the species' nesting ecology. We studied the ecology of breeding White-faced Ibis from May through August 1995 on Lower Klamath National Wildlife Refuge (NWR) and surrounding private agricultural lands of northern California and southern Oregon. On Lower Klamath NWR we monitored the breeding success of 126 nests located in four colonies. Colony sizes ranged from 12 to 1,149 pairs, with an estimated 2,041 total pairs of breeding ibises nesting exclusively in early successional hardstem bulrush (Scirpus acutus). Nest initiation dates ranged from 10 May to 28 June and mean clutch size was 3.14. Overall reproductive success was high, averaging 85% nest success during the incubation period (n = 119), 82% hatchability, 97% whole and partial brood survival, and 2.06 fledglings produced per nest. The Mayfield estimate of nest success was 79.1% during the incubation period (n = 126), and 95% during the nestling period (n = 113). We observed up to 84% of the breeding population traveling north of the refuge to forage on private agricultural lands. In agricultural habitats outside of the refuge, foraging ibis preferred flooded grazed cattle pasture. Although adult ibis were significantly more efficient at foraging in wetlands than were juveniles, the two age classes were equally proficient at foraging in pasturelands. Our apparent nest success estimates (85%) are some of the highest reported anywhere in the literature for White-faced Ibis. Moreover, livestock pastures offered valuable foraging habitats to breeding ibis throughout the nesting cycle. We suggest that among breeding localities within the Great Basin, Lower Klamath NWR has great potential to become a significant breeding stronghold for White-faced Ibis in the future.

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Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Created Date December 11, 2019
Metadata Updated Date December 11, 2019

Metadata Source

Harvested from DOI CKAN Harvest Source

Additional Metadata

Resource Type Dataset
Metadata Created Date December 11, 2019
Metadata Updated Date December 11, 2019
Publisher Fish and Wildlife Service
Unique Identifier FWS_ServCat_60416
Brent Frakes
Maintainer Email
Public Access Level public
Bureau Code 010:18
Metadata Context
Metadata Catalog ID C:\Program Files (x86)\FWS\DataStore\Application\OpenData\FWS_ServCat_v1_1.json
Schema Version
Catalog Describedby
Harvest Object Id 310fa706-83a5-4320-a263-9d47aa75e80a
Harvest Source Id 34ce571b-cb98-4e0b-979f-30f9ecc452c5
Harvest Source Title DOI CKAN Harvest Source
Data First Published 1995-01-01
Homepage URL
Data Last Modified 1995-01-01
Program Code 010:094, 010:028
Related Documents ""
Source Datajson Identifier true
Source Hash 2c848522f6e70eb0404f3eddc2f2efed88ee2608
Source Schema Version 1.1
Spatial -122.096222,41.793705,-121.0586,43.0671844
Temporal 1995-05-01/1995-08-01
Category "Unpublished Report"

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