10.5061/DRYAD.J6F4858
Cruz, Jennyffer
University of Wisconsin-Madison
Windels, Steven K.
Voyageurs National Park International Falls Minnesota
Thogmartin, Wayne E.
United States Geological Survey
Crimmins, Shawn M.
University of Wisconsin–Stevens Point
Grim, Leland H.
Voyageurs National Park International Falls Minnesota
Larson, James H.
United States Geological Survey
Zuckerberg, Benjamin
University of Wisconsin-Madison
Data from: Top-down effects of repatriating bald eagles hinder jointly
recovering competitors
Dryad
dataset
2019
bottom-up
predator recovery
rewilding
osprey
heron
multispecies management
2019-04-11T20:34:15Z
2019-04-11T20:34:15Z
en
https://doi.org/10.1111/1365-2656.12990
653444 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
1. The recovery of piscivorous birds around the world is touted as one of
the great conservation successes of the 21st century, but for some
species, this success was short-lived. Bald eagles, ospreys, and great
blue herons began repatriating Voyageurs National Park, USA, in the
mid-20th century. However, after 1990, only eagles continued their
recovery, while osprey and heron recovery failed for unknown reasons. 2.
We aimed to evaluate whether top-down effects of bald eagles, and
bottom-up effects of inclement weather, habitat quality, and fish
resources contributed to the failed recovery of ospreys and herons in a
protected area. 3. We quantified the relative influence of top-down and
bottom-up factors on nest colonization, persistence (i.e., nest reuse) and
success for ospreys, and occurrence and size of heronries using 26 years
(1986-2012) of spatially-explicit monitoring data coupled with
multi-response hierarchical models and Bayesian variable selection
approaches. 4. Bald eagles were previously shown to recover faster due to
intensive nest protection and management. Increased numbers of eagles were
associated with a reduction in the numbers of osprey nests, their nesting
success, and heronry size; while higher local densities of nesting eagles
deterred heronries nearby. We found little evidence of bottom-up
limitations on the failed recovery of herons and ospreys. 5. We present a
conservation conundrum: bald eagles are top predators and a flagship
species of conservation that have benefited from intensive protection, but
this likely hindered the recovery of ospreys and herons. Returning top
predators, or rewilding, is widely promoted as a conservation strategy for
top-down ecosystem recovery, but managing top predators in isolation of
jointly recovering species can halt or reverse ecosystem recovery.
Previous studies warn of the potential consequences of ignoring biotic
interactions amongst recovering species, but we go further by quantifying
how these interactions contributed to failed recoveries via impacts on the
nesting demography of jointly recovering species. Multi-species management
is paramount to realizing the ecosystem benefits of top predator recovery.
Observed nest occupancy, success and number of fledged young for osprey
during 1973-2012Nest occupancy, success and number of fledged young for
osprey in Voyageurs National Park observed during 1973-2012 from aerial
surveys. Predictors associated with each nest include descriptors for
weather, ice-out dates, nest and foraging habitat, fish resources and
various measures of potential intraguild predation and competition from
bald eagles.OspreyData_JAE.xlsxHeronry occupancy and number of nests of
great blue herons observed during 1973-2012Heronry occupancy and number of
nests of great blue herons in Voyageurs National Park observed during
1973-2012 from aerial surveys. Predictors associated with each heronry
include descriptors for nesting and foraging habitat, fish resources and
various measures of potential intraguild predation and competition from
bald eagles and osprey.HeronData_JAE.xlsx