DOI: 10.5061/dryad.0k6djhb8q
title: Data from: Wood ducks and hooded mergansers as interspecific brood parasites: An evaluation of parasitic egg survival

description: Conspecific and interspecific brood parasitism are alternate reproductive
 strategies more pervasive in waterfowl than in any other group of birds.
 While previous research has measured costs incurred by nest hosts
 incubating parasitized clutches, few studies have focused on the relative
 success of parasites. Here, we evaluated the success of wood duck (Aix
 sponsa) and hooded merganser (Lophodytes cucullatus) eggs laid
 parasitically in Louisiana and Mississippi. We monitored nest boxes,
 assigned eggs in each nest as host or parasitic, and determined the number
 of eggs that hatched and failed. Across all study areas (1994–1999 and
 2020–2023), we monitored 1750 wood duck and 377 hooded merganser nests;
 ~13% of wood duck and ~24% of hooded merganser nests were
 interspecifically parasitized. We modeled egg survival of 2925 host and
 691 parasitic eggs from 197 successful nests (≥1 hatched egg, regardless
 of species). Wood duck eggs laid in hooded merganser nests had lower
 survival [0.293, CI = 95% credible intervals (after, CI) = 0.176, 0.439]
 than hooded merganser eggs (0.762, CI = 0.704, 0.810) laid in wood duck
 nests. Clutch size negatively influenced parasitic wood duck egg survival
 (β = −.24, CI = −0.39, −0.10) but had a slight positive influence on
 parasitic hooded merganser eggs (β = .08, CI = 0.04, 0.12). Our results
 revealed that hooded merganser eggs experience higher success when laid
 parasitically in wood duck nests, whereas wood duck eggs experience lower
 success when laid parasitically in hooded merganser nests. Our results
 reveal new complexity in waterfowl interspecific brood parasitism, where
 the success of parasitic eggs is species‐, host‐, and context‐specific.
description: # Data from: Wood ducks and hooded mergansers as interspecific brood
 parasites: An evaluation of parasitic egg survival ## Article DOI
 [10.1002/ece3.11721](10.1002/ece3.11721) ## Cite this dataset
 [https://doi.org/10.5061/dryad.0k6djhb8q](https://doi.org/10.5061/dryad.0k6djhb8q) Metadata used for evaluating the survival of parasitic wood duck and hooded merganser eggs laid interspecifically; published by Bakner et al. 2024. This manuscript has been accepted for publication by Ecology and Evolution in 2024. #### DATAFILES ###### *analysis.R* This file contains R code that can be used to reproduce the analysis and numbers listed in the results section of manuscript. Stored on Zenodo ###### *cleanData6.6.24.csv* This file is the data frame that can be read into program R to execute the code file listed above. This data frame contains several columns which are described below: 1. id - nest identifier 2. HOST - nest host with "1" = wood duck and "2" = hooded merganser 3. Nest - type of nest with "WD" = wood duck nest containing only wood duck eggs, "HM" = hooded merganser nest containing on hooded merganser eggs, and "MI" = nests containing both wood duck and hooded merganser eggs 4. type - indicates whether the row contains information on host eggs or parasitic (listed in data frame as "parasite") eggs 5. STUDY - study site identifier 6. State - state identifier 7. clutch - total number of eggs in clutch 8. hatch - total number of eggs that hatched from clutch 9. total_clutch - total number of eggs in clutch (i.e., host and parasitic combined) 10. NESTFATE - indicates weather the nest hatched at least 1 egg or failed completely 11. inc - indicates weather a clutch was incubated or not 12.  BOX_TYPE - indicates nest box size