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Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73 (S2): e64520, mayo 2025 (Publicado May. 15, 2025)
Habitat complexity influenced mixed-species bird flock
composition and occurrence in highlands
Pablo Muñoz1, 2; https://orcid.org/0000-0002-3030-1010
Luis Sandoval1, 3*; https://orcid.org/0000-0002-0793-6747
1. Laboratorio de Ecología Urbana y Comunicación Animal, Escuela de Biología, Universidad de Costa Rica, San José,
Costa Rica; biosandoval@hotmail.com (*Correspondencia); pablomgl94@gmail.com
2. Organización para Estudios Tropicales. Oficina de Costa Rica, Universidad de Costa Rica, San José, Costa Rica.
3. Colección de Ornitología, Museo de Zoología, CIBET, Universidad de Costa Rica, San José, Costa Rica.
Received 20-VIII-2024. Corrected 15-I-2025. Accepted 04-III-2025.
ABSTRACT
Introduction: Mixed-species bird flocks are groups that change rapidly throughout the day, influenced by factors
such as resource availability, vocalizations, and habitat complexity. Habitat complexity can either enhance or limit
interspecific interactions by increasing the number of species or individuals that interact. However, variations in
habitat structure are often overlooked when studying mixed-species flock composition, leading to incomplete or
unrealistic interpretations of factors influencing flock composition.
Objective: This study aims to investigate the relationship between the composition and occurrence of mixed-
species bird flocks and the habitat complexity of a highland forest in Costa Rica.
Methods: We conducted this study along a 5.5 km transect in the highland area of Braulio Carrillo National Park
in Heredia, Costa Rica (10°05’ N & 84°04’ W; 2 100 m a.s.l.) from March to December 2019. Mixed-species flocks
were surveyed twice weekly from 06:00 to 11:00 h. Habitat complexity was assessed using 16 plots (10x10 m)
distributed across the study area to capture most of the habitat variation. We estimated the probability of occur-
rence at different habitat types for mixed-species flock that vary in sizes using kernel density estimation in QGIS.
Results: A total of 34 species were recorded across 125 mixed-species flocks, categorized into 50 small-sized,
46 medium-sized, and 30 large-sized flocks. Flock sizes were associated with different habitat characteristics.
A positive association was found between higher canopy and understory cover, tree quantity, and diameter at
breast height (DBH) with species composition and abundance in large-sized flocks, but not in medium- and
small-sized flocks.
Conclusion: While the overall presence of mixed-species flocks was not limited by habitat structure, their size
and composition were significantly associated with habitat.
Key words: endemic birds; highland birds; oak forest; peat bogs; tanagers.
RESUMEN
La complejidad del hábitat influencia la composición y la ocurrencia
de bandadas mixtas de aves en las tierras altas
Introducción: Las bandadas de aves mixtas son grupos que cambian rápidamente a lo largo del día, influenciados
por factores como la disponibilidad de recursos, vocalizaciones y complejidad del hábitat. La complejidad del
hábitat puede favorecer o limitar las interacciones interespecíficas al aumentar el número de especies o indivi-
duos que interactúan. Sin embargo, las variaciones en la estructura del hábitat a menudo no se incluyen cuando
https://doi.org/10.15517/rev.biol.trop..v73iS2.64520
SUPPLEMENT
SECTION: ECOLOGY
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INTRODUCTION
Habitat complexity, defined as the physi-
cal structure of the habitat (Carter et al., 2018),
significantly influences species assembly and
their interactions within a community, rang-
ing from parasite-host dynamics to food webs
and predator-prey interactions (Carter et al.,
2018; Kovalenko et al., 2012; Staniczenko et al.,
2017). Species interactions may be enhanced in
habitats with high complexity, as the abundant
microhabitats and resources support a greater
number and diversity of species (Maldonado-
Coelho & Marini, 2000; Maldonado-Coelho
& Marini, 2004). Community interactions are
often assessed under the assumption of homo-
geneity in individual and habitat structure,
overlooking their variations and leading to
incomplete insights or unrealistic interpreta-
tions (Carter et al., 2018). Therefore, it is
crucial to consider this variation, as heteroge-
neity is essential for understanding the driv-
ers of complex communities (Carter et al.,
2018; Gibert & Brassil, 2014; Mokross et al.,
2018). This is particularly relevant when study-
ing bird communities, which not only utilize
habitat structures differently but also tend to
form complex interspecies associations, such
as mixed-species flocks within these habitats
(Jones & Robinson, 2021).
Mixed-species flocks of birds are among
the most common and interactive group sys-
tems in nature (Goodale et al., 2020; Morse,
1970). These flocks are dynamic assemblages
with both positive and negative interactions
(Goodale et al., 2020). Understanding how they
are established, maintain cohesion, and interact
intra-specifically (Jones et al., 2020) is central
to community ecology. The most commonly
reported interactions within mixed-species
flocks include behavioral interactions (Morse,
1970), role turnovers (Farine, 2021), and spe-
cies facilitation in joining the flock (Martínez et
al., 2018; Muñoz 2022). Role turnovers within
the flock occur when the relative population of
a species increases in the area, like Atlapetes tib-
ialis that becomes a gregarious species outside
the breeding season and assumes a leadership
role in mixed-species flocks (Muñoz 2022).
Facilitation occurs when members of the flock
display behaviors that trigger flocking, such
as specific vocalizations (Pagani-Nuñez et al.,
2018), and can also result from external factors
like habitat complexity (Croft et al., 2011; Goo-
dale et al., 2010).
Habitat complexity may facilitate flocking
behavior in various ways. For instance, specific
habitat traits (e.g., background conspicuous-
ness) influence signal transmission and its
se estudia la composición de las bandadas de especies mixtas, lo que lleva a interpretaciones incompletas de los
factores que influyen en la composición de la bandada.
Objetivo: Este estudio tiene como objetivo investigar la relación entre la composición y la ocurrencia de bandadas
mixtas de aves y la complejidad del hábitat de un bosque de tierras altas en Costa Rica.
Métodos: Realizamos este estudio a lo largo de un transecto de 5,5 km en el Parque Nacional Braulio Carrillo
en Heredia, Costa Rica (10°05’ N & 84°04’ O; 2 100 m s. n. m.) de marzo a diciembre de 2019. Las bandadas de
especies mixtas se muestrearon dos veces por semana de 06:00 a 11:00 h. La complejidad del hábitat se evaluó
utilizando 16 parcelas (10x10 m) distribuidas en el área de estudio para capturar la mayor variación de los hábitat.
Estimamos la probabilidad de ocurrencia en diferentes tipos de hábitat para bandadas de especies mixtas que
varían en tamaño utilizando la estimación de densidad kernel en QGIS.
Resultados: Se registraron un total de 34 especies en 125 bandadas de especies mixtas, categorizadas en 50 banda-
das de tamaño pequeño, 46 de tamaño mediano y 30 de tamaño grande. Los tamaños de las bandadas se asociaron
con diferentes características del hábitat. Se encontró una asociación positiva entre una mayor cobertura de dosel
y sotobosque, cantidad de árboles y diámetro a la altura del pecho (DAP) con la composición y abundancia de
especies en bandadas de tamaño grande, pero no en bandadas de tamaño mediano y pequeño.
Conclusión: Si bien la presencia general de bandadas de especies mixtas no estuvo limitada por la estructura del
hábitat, su tamaño y composición se asociaron significativamente con el hábitat.
Palabras clave: aves endémicas; aves de las tierras altas; bosques de robles; turberas; tangaras.
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Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73 (S2): e64520, mayo 2025 (Publicado May. 15, 2025)
reception by conspecifics and heterospecifics
(Munn, 1985; Uy & Stein, 2007). Moreover,
habitat structural traits, such as forest height
and area size, influence the gregariousness of
mixed-species flocks (Mokross et al., 2014),
as they can physically limit the number and
identity of species joining a flock and affect the
cost-benefit tradeoff for potential flock mem-
bers. For example, the absence of larger trees
limits the occurrence of woodcreepers, which
used them to forage or establish a territory
(Darrah & Smith, 2013; Maldonado-Coelho &
Marini, 2000), while the lack of dense under-
story restricts wrens and antbirds that rarely
move into open areas (Mokross et al., 2018).
Other aspects of forest structure that might
affect mixed-species flock composition, such
as resource availability (e.g., fruits or flow-
ers), shelter (e.g., abundance and size of trees),
or specialized foraging structures (e.g., dense
understory, canopy cover), have not been fully
considered (Hutto, 1988; Jones, & Robinson,
2021; Kotagama & Goodale, 2004; Mangini et
al., 2023b). Changes in these habitat traits may
trigger composition effects on mixed-species
flock structure. Reduced availability of under-
story resources may decrease the complexity
of mixed-species flocks by reducing the over-
all foraging efficiency of bird species (Hutto,
1988). Additionally, a complex habitat structure
with a higher canopy and cover may provide
more usable habitat space for bird species when
moving in a mixed-species flock (Mokross et
al., 2014). Changes in habitat complexity, such
as higher or lower understory cover, can also
limit the species that can potentially join the
mixed-species flock due to reduction of forest
cover for them (Rutt et al., 2020).
Habitat complexity varies significantly
not only at a large scale, but also over short
distances within the same area (Rutt et al.,
2020) and this will affect directly the composi-
tion and level of association of mixed-species
flocks. Our objective is therefore to describe
the correlation between the composition and
occurrence sites of mixed-species flocks with
the habitat complexity (structure) of a high-
land forest. Costa Rican highlands are suitable
to answer this question because they present
mixed-species flocks all year round with its
members interacting among them at all times
(Powell, 1979; Powell, 1985). In addition, tropi-
cal mixed-species flocks tend to use all forest
structures present in its habitat, like branches,
trunks, mosses, understory cover, and treetops
(Powell, 1985).
MATERIALS AND METHODS
We conducted this study along a 5.5 km
transect (Fig. 1) in the highland area of Braulio
Carrillo National Park in Heredia, Costa Rica
(10°05’N & 84°04’W; 2100 m a.s.l.) from March
to December 2019. The study area includes
Fig. 1. A. The red dot is the study location area in Costa Rica. B. Study area map with the transect used for sampleing
highlited in white.
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a mix of oak (Quercus sp.) and Andean alder
(Alnus acuminata) forest, secondary growth
areas (dominated by bamboos, Malvaceae’s
trees and bushes, and Ericaceae bushes), and
several disturbed areas featuring pastures, peat
bogs, and isolated trees. These features create a
heterogeneous landscape that allowed compari-
sons between mixed-species flocks structure
according to the habitat composition.
We searched for mixed-species flocks twice
per week from 06:00 to 11:00 h, along the
transect (Fig. 1). To minimize potential biases
related to time and location, we alternated the
starting point each day, beginning each sam-
pling session at the opposite end of the transect
from the previous one. Whenever we encoun-
tered a flock, we followed for 10 min and
recorded the maximum number of individuals
per species during this time period. The geo-
graphical position of each flock was recorded
at the beginning and end of this period using a
Garmin 64s GPS device.
We separated the mixed-species flocks in
three groups based on the number of individu-
als and species (Chen & Hsieh, 2002; Mangini
et al., 2023a). Small-size mixed-species flocks
included <4 species or <8 individuals. Medium-
size mixed-species flocks included 5-6 species
or 9-11 individuals. Large-size mixed-species
flocks included >7 species or >12 individuals.
This imformation allowed us to compare if size
of mixed-species flocks size varied according to
habitat structure and characteristics.
Relationship between flocks and habi-
tats: To measure habitat complexity traits, we
used 16 plots of 10x10 m distributed across
the study area to cover most common habitat
types present (Fig. 1). Half of the plots were
located near the transect (<50 m from the
transect edge) where mixed-species flocks were
sampled, and the other half of the plots were
located at least 200 m away from the transects.
We placed the plots ensuring a minimum dis-
tance of 200 m between them and to have four
replicates in each habitat types present in the
study area: pastures/peat bogs, old-growth for-
est, forest plantation, and secondary forest. In
each plot, we counted all trees with the diam-
eter at breast height (DBH) greater than 10 cm
and measured the exact DBH for each one. We
recorded canopy height at three points within
the plot (one at the center and two sides) using
a laser rangefinder. Additionally, we selected
four equidistant 1x1 m sub-plots within each
plot and estimated understory coverage as a
percentage of ground cover by dead leaves,
branches, and plants, but not grasses. Finally,
we measured the leaf area index (LAI) using
five photos per plot, following the method
published by Martin (2015). The photos were
taken with a Canon SL1 camera and an 18-55
mm lens: four photos directed at each cardinal
point at a 45-degree angle and one photo at a
90-degree angle towards the canopy. For the
eight plots near the trail, we placed 1x1 m sub-
plots to measure understory cover at each of
the four corners of the 10x10 m plots. For the
eight plots farther from the trail, we positioned
the 1x1 m sub-plots along the sides of the 10x10
m plots, midway between each corner. Using
the data gathered from all 16 plots, we inter-
polated habitat structure traits to the rest of
the un-sampled area using the inverse distance
weighting method in QGIS (QGIS Develop-
ment Team, 2021). This created a separate layer
for each habitat structure trait measured, cover-
ing the entire study area (Fig. 2), and allowed
us to: 1) determine the suitability of different
habitat structures in the study area for each
mixed-species flock, and 2) assign the habitat
structure where each observed flock occurred.
Before analyzing the mixed-species flock
occurrence, we ensured that each flock includ-
ed in the analysis were at least 10 m apart from
other flock. We used this distance because the
predictor layers employed were interpolated to
10x10 m pixels. We estimated the probability
of occurences of each mixed-species flock size
group in the study area using kernel density
estimation in QGIS (QGIS Development Team,
2021). For this, we mapped the occurences of
each mixed-species flock size on top the five
cover layers of habitat complexity (see above),
and created three probability map models, one
for each mixed-species flock size. Finally, we
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Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73 (S2): e64520, mayo 2025 (Publicado May. 15, 2025)
used the GPS position of each mixed-species
flock to quantify its occurrence in each main
habitat of the study area: pasture/peat bogs, old-
growth, forest plantation, and secondary forest;
according to habitat observed in Google maps
on January 2020, and in cases where habitat was
covered by clouds we assigned the category of
unknown habitat.
Statistical analysis: First, we conducted
three chi-square test to compare if each mixed-
species flock group-size used different the main
habitats (i.e., pasture/peatbogs, old-growth, for-
est plantation, and secondary forest). Second,
we compared if the habitat structure where each
mixed-species flock group-size occurred varied
using a multiple analysis of variance (MANO-
VA). For this analysis, we used as our indepen-
dent variable the flock size category. We used
as dependent variables the values of each of the
five habitat structure measurements (i.e., DBH,
canopy height, tree abundance, understory cov-
erage, and LAI) where each flock occurred.
This value was estimated using the layer for
each habitat strcture trait built using the inverse
distance weighting method in QGIS. For this
analysis, we used a posterior comparison to
report which habitat structure variable were
diferent between mixed-species flock group-
size. Third, we conducted a non-metric mul-
tidimensional scaling (NMDS) analysis with
Euclidian distance and 10 000 permutations
to compare if the mixed-species flock groups
varied in composition (i.e., species and abun-
dance) and its relationship with the five habitat
structure variables. Finally, we used a one-way
PERMANOVA to analyze if the three mixed-
species flock groups were significantly different
in the NMDS, and with pair-wise comparison
we analyzed differences between flock sizes.
All statistical analysis were conducted using
PAST 4.17 (https://www.nhm.uio.no/english/
research/resources/past/).
RESULTS
We recorded 34 species in 127 mixed-spe-
cies flocks, with 51 classified as small-size, 46
as medium-size, and 30 as large-size (Table 1,
Appendix 1). We found that each mixed-species
Fig. 2. Inverse weighted interpolations of habitat structure variables for the whole area; A. Understory cover, B. Tree height,
C. Diameter at breast height, D. Number of trees, and E) Leaf area index. Red indicates higher values of the variable, while
the blue indicates lower values of the variable.
6Revista de Biología Tropical, ISSN: 2215-2075 Vol. 73 (S1): e64520, mayo 2025 (Publicado May. 15, 2025)
flock size used differently the four main habi-
tats in the study area. Small-size mixed-species
flocks used in similar frequency the four main
habitats of the study site (Χ² = 0.80, df = 3, P
= 0.85; Table 1). Medium-sized mixed-species
flocks used more old-growth and forest plan-
tations than the other two main habitats (Χ²
= 8.84, df = 3, P = 0.03; Table 1). Meanwhile,
large-size mixed-species flocks used more for-
est plantations and pasture/peat bog habitats
than the other two main habitats (Χ² = 12.30,
df = 3, P = 0.006; Table 1).
Each mixed-species flock group sizes
occurred in sites with different habitat struc-
ture according to the five measurements took
(MANOVA: Wilk’s λ = 0.92, F8,438 = 2.26, P
= 0.02; Fig. 3). Among the habitat structure
variables analyzed independently with the pos-
terior comparisons of the MANOVA, only the
diameter at breast height (DBH) showed a sig-
nificant difference between mixed-species flock
group sizes (F2, 222 = 3.70, P = 0.03). Large-size
mixed-species flocks were more often found in
sites with larger DBH compared to the other
two mixed-species flock group sizes (Fig. 4).
Meanwhile, the mixed-species flock group sizes
used sites with similar values for the other four
habitat structure variables (F2,222 < 0.82, P >
0.44 for all variables; Fig. 4).
We found a positive association between
higher canopy and understory cover, tree quan-
tity, and DBH with species composition and
abundance per species in large-size mixed-
species flocks (PERMANOVA: F = 4.60, P <
0.001; Fig. 4). However, small and medium-size
Table 1
Percentage of occurrence of mixed-species flock size in
different habitat types.
Habitat Type Small
(%)
Medium
(%)
Large
(%)
Pasture/Peatbogs 20.8 15.7 34
Old-growth 23.1 27.8 14.9
Forest Plantation 19.8 32.5 40.4
Secondary Forest 15.4 7.2 2.1
Unknown 20.8 16.9 8.5
Fig. 3. Kernel density estimation models for A. Small-sized,
B. Medium-sized, and C. Large-sized mixed-species flocks.
Red indicates higher probabilities that each flock size occur
in that site, while blue indicates lower probabilities of the
occurrence.
mixed-species flocks were associated with sites
that showed higher values of leaf area index
(LAI; Fig. 4). Additionally, small and medium-
size mixed-species flocks had similar species
composition and abundance per species (pair-
wise comparison: P = 0.13), but both differed
significantly from large-size mixed-species
flocks (small vs. large: P < 0.001, medium vs.
large: P < 0.001; Fig. 4).
DISCUSSION
Habitat structure affects the size of flocks
that occur in different sites of the study area.
This pattern was expected, since more complex
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Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73 (S2): e64520, mayo 2025 (Publicado May. 15, 2025)
habitat structures facilitate larger mixed-species
flocks by accommodating species with varying
microhabitat preferences, such as understory
specialists or foraging specialists (Zhang et al.,
2013; Zuluaga & Rodewald, 2015). For instance,
woodcreepers require large trees with mosses
and bromeliads, commonly found in old sec-
ondary forests and plantations in the study area,
to join the flocks (Cintra et al., 2006; Rodrigues
et al., 2016). Additionally, wrens need dense
understories to establish territories and join
flocks as they pass through (Caro et al., 2013;
Shogren et al., 2019). Consequently, habitats
with a greater variety of complex structures
(e.g., higher canopy and understory coverage,
and more trees) allowed more species to join
the flocks. This explain why we observed more
medium and large mixed-species flocks in areas
with forest plantations and old-growth forests
(Zuluaga & Rodewald, 2015). However, large
mixed-species flocks were also found in higher
numbers in open disturbed areas (i.e., pastures/
peat bogs), which have less complex habitat
characteristics (Harris et al., 2018; Lindgren et
al., 2018). This fiding can be explained by the
fact that large flocks in open areas increased
in size by adding more individuals of the same
species, rather than different species as seen in
forest habitats (pers. obs.). This occurs because
species that inhabit in open areas (i.e., mixed-
species core species) and form mixed-species
flocks are typically more numerous such as
chlorospingus and warblers (Blake & Loiselle,
2001). Contrary to previous reports from
another tropical forest, where flock complexity
(i.e., more individuals and species) increased on
advanced forest successional stages (Zhang et
al., 2013). Consequently, our highland mixed-
species flock system showed that large-size
flocks may occurr on both old forest planta-
tions and peat bogs
Conversely, small mixed-species flocks
occurred in similar abundance across all habitat
types. This is because the core species that form
Costa Rican highland mixed-species flocks
(e.g., Tangara dowii, Chlorospingus pileatus,
Margarornis rubiginosus, and Atlapetes tibialis,
Appendix 1) are present in all habitats, includ-
ing open areas, forest edges, secondary forests,
and plantations (Barrantes, 2009; Barrantes et
al., 2011; Stiles & Skutch, 1989). Additionally,
species from genera that did not usually involve
in mixed-species flocks in lowlands as Turdus,
Piranga and Atlapetes that are common in
open areas and secondary forest canopies also
join mixed-species flocks (Bohórquez, 2003,
Powell, 1979, Stiles & Skutch, 1989), probably
because increase the food intake and decrease
Fig. 4. Non-Metric Multidimensional Scaling (NMDS) plot showing the position of different mixed-species flocks sizes and
its relationship with the habitat complexity variables. Error bars represent one standar error in both axes.
8Revista de Biología Tropical, ISSN: 2215-2075 Vol. 73 (S1): e64520, mayo 2025 (Publicado May. 15, 2025)
the probabilities of predation (Hino, 2000;
Mangini et al., 2023b). Consequently, mixed-
species flocks occurrences are not limited by
habitat structure in highlands (Barrantes et al.,
2011) and occurred in all the sites, allowing
small-size flocks use all habitats available in the
study area.
When comparing habitat complexity and
its relationship with flock composition, we
found that medium and large-sized flocks did
not respond uniformly and used microhabitat
inside the four habitat types of the study area
differently. While, medium-sized flocks were
more similar in structure and habitat use to
small-sized flocks. This similarity may be due
to both flock sizes sharing more species and
having similar numbers of individuals per spe-
cies (Appendix 1), especially if both are primar-
ily composed of core flock species that tend to
forage on substrates such as isolated trees, forest
edges, and mature forests (Barrantes & Pereira,
2002; Stiles & Skutch, 1989). Abrupt changes
in habitat structure over short distances (e.g.,
transitioning from old-growth forest or for-
est plantation to open areas), as observed in
the study area (Fig. 1), affected the number
of species in our mixed-species flocks but not
the number of individuals. Forest-dependent
species (e.g., woodcreepers, tapaculos, wrens)
would abandon the mixed-species flocks upon
reaching open areas (Rutt et al., 2020), while
core species continued foraging together across
different habitats. Consequently, the num-
ber and type of species that form small and
medium-size flocks were more similar to each
other than to larger flocks. In other environ-
ments, such as the Amazonian lowlands, abrupt
changes in habitat structure generally limit
the movement of mixed-species flocks because
their core species are more forest-dependent
than what we found for Costa Rican highland
species (Rutt et al., 2020). Therefore, on those
sites mixed-species flocks composition in each
habitat type are different, showing a greater
association between the species that form the
mixed-species flocks and the habitats in which
they occur (Zhang et al., 2013).
We concluded that the presence of mixed-
species flocks as a whole was not limited by for-
est structures in the study area, but their sizes
and composition were associated with habitat
complexity. Forest structures with more micro-
habitats for species to forage may enhance the
occurrence of large-size mixed-species flocks
in an area. A core set of species that joined
mixed-species flocks are consistent across all
forest types and flock sizes, which may explain
why these flocks were present throughout the
study area. Forest structure likely might also
affect the number and type of interactions of a
flock members, but this is an aspect the remain
understudied (Zhang et al., 2013).
Ethical statement: the authors declare that
they all agree with this publication and made
significant contributions; that there is no con-
flict of interest of any kind; and that we fol-
lowed all pertinent ethical and legal procedures
and requirements. All financial sources are fully
and clearly stated in the acknowledgments sec-
tion. A signed document has been filed in the
journal archives.
See supplementary material
a02v73s2-suppl1
ACKNOWLEDGMENTS
We thank the Association of Field Ornitho-
logists, the Centro de Investigación en Bio-
diversidad y Ecología Tropical (CIBET), and
Vicerrectoría de Investigación of the University
of Costa Rica (grant number B9123 y C3118).
We also thank Rafa Molina for helping in a lot
of the field trips. We were funded by the Asso-
ciation of Field Ornithologists with the Alexan-
der Bergstrom Memorial Research Award given
to PM and the Vicerrectoría de Investigación
of the University of Costa Rica with the grant
number B9123 and C3118 to LS. We declare
there is no conflict of interest.
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Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73 (S2): e64520, mayo 2025 (Publicado May. 15, 2025)
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