DOI: 10.5061/dryad.51c59zwf7
title: Data for: Waterbird abundance in aquaculture ponds: the significance of day and night and pond type

description: The loss of coastal wetlands represents a grave threat to waterbirds,
 prompting the use of artificial wetlands, such as aquaculture ponds, as a
 means of conservation. Aquaculture ponds are common in coastal areas and
 provide production value and ecological function as waterbird habitats.
 However, certain piscivorous birds may cause economic losses to the
 aquaculture industry. Different types of ponds provide habitat for various
 bird assemblages, and waterbirds exhibit nocturnal feeding behavior and
 utilize habitats distinct from those used during the day. Most waterbird
 surveys were conducted during the daytime, limiting our understanding of
 their nocturnal habitat utilization. This study conducted diurnal and
 nocturnal surveys on shorebirds, waterfowl, and Black-crowned Night Heron
 (Nycticorax nycticorax) ten times in three aquaculture ponds situated in
 the Cigu District of Tainan, namely fish/shrimp, hard clam, and abandoned
 ponds between October 2021 and November 2022. The results showed no
 significant difference in shorebird density between day and night.
 However, shorebird density in fish/shrimp ponds was the highest and
 significantly higher than in abandoned ponds. Conversely, waterfowl
 density exhibits a significant increase in abandoned ponds compared to the
 other two pond types, irrespective of diurnal or nocturnal conditions.
 Furthermore, waterfowl density in abandoned ponds is significantly higher
 during daylight hours compared to the nocturnal period. In the daytime,
 the density of night herons was significantly higher in abandoned ponds
 than in the other two ponds. Nevertheless, during nighttime hours,
 fish/shrimp ponds exhibit the highest density of Black-crowned Night
 Herons, significantly surpassing that found in hard clam ponds. Notably,
 water coverage also influences the density of both shorebirds and
 waterfowl. The foraging frequency of waterfowl and night herons was
 greater during nocturnal hours, while shorebirds did not exhibit
 significant variations between day and night. Consequently, this study
 underscores the significance of considering both diurnal and nocturnal
 habitats in formulating strategies for waterbird conservation.
description: The aquaculture ponds in our study were
 classified into three types: fish/shrimp ponds, hard clam ponds, and
 abandoned ponds. Fish/shrimp ponds were utilized for cultivating milkfish,
 grouper, or white shrimp. These ponds, along with hard clam ponds,
 constituted the primary types of aquaculture in the study area, while
 abandoned ponds offered a semi-natural marsh environment. Field surveys
 were conducted ten times between October 2021 and November 2022,
 specifically in October, November, December 2021, January, February,
 March, May, July, September, and November 2022. Each survey round was
 carried out by a team of two experienced surveyors, who completed the
 surveys within two days. Surveyors recorded the bird species (or taxa),
 quantity, behavior (foraging/non-foraging), and water coverage (%) of each
 sampled pond. Water coverage was classified into four categories: low
 (0–30%), moderate (&gt;30–60%), high (&gt;60–90%), and full
 (&gt;90%). To minimize disturbance to waterbirds, surveyors conducted
 daytime surveys from inside their vehicles using binoculars and telescopes
 between 10 a.m. and 4 p.m. Night surveys were conducted on the same day as
 the daytime surveys, from 6 p.m. to 10 p.m., using a handheld thermal
 imaging camera (FLIR T560 with a 6° lens). Waterbirds were classified into
 at least three groups: shorebirds, waterfowl, and
 night-herons.
description: # Data for: Waterbird abundance in aquaculture ponds: the significance of
 day and night and pond type
 [https://doi.org/10.5061/dryad.51c59zwf7](https://doi.org/10.5061/dryad.51c59zwf7) Our bird survey conducted diurnal and nocturnal surveys on shorebirds, waterfowl, and Black-crowned Night Heron ten times in three types of aquaculture ponds situated in the Cigu District of Tainan between October 2021 and November 2022. The data contain year, month, aquaculture pond id, aquaculture pond area (ha), aquaculture pond type (fish/shrimp, hard clam, abandoned), time (day, night), water coverage (full, high, moderate, low), waterbird (shorebirds, waterfowl, night heron) and count.