Ecological and evolutionary significance of molt in lowland Neotropical landbirds

Abstract The slow-paced life history of many Neotropical birds (e.g., high survival and low fecundity) is hypothesized to increase lifetime fitness through investments in self-maintenance over reproduction relative to their temperate counterparts. Molt is a key investment in self-maintenance and is readily shaped by environmental conditions. As such, variation in molt strategies may be a key mechanism underlying life-history trade-offs and adaptation to new environments. Here, we review molt strategies from a diversity of lowland Neotropical landbirds and examine how variation in molt strategies, characterized by differences in molt insertions, timing, extent, and duration contribute to life-history variation and adaptation to diverse ecological conditions. In addition to our synthesis, we present a case study to examine the relationship between home range size and duration of the definitive prebasic molt of a well-studied subset of Amazonian landbirds. Our results suggest a connection between prolonged molt duration and larger home range size of small-to-medium-sized Amazonian landbirds. Our aims were to identify key gaps in our knowledge of Neotropical bird molt, to stimulate further comparative studies into the evolution of molt strategies, and to highlight how variation in molt strategies may be a key mechanism underlying life-history variation across latitudes.

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Green morays (Gymnothorax funebris) have sedentary ways in mangrove bays, but also ontogenetic forays to reef enclaves

Environmental Biology of Fishes ◽

10.1007/s10641-021-01137-0 ◽

2021 ◽

Author(s):

Matthew S. Kendall ◽

Laughlin Siceloff ◽

Ashley Ruffo ◽

Arliss Winship ◽

Mark E. Monaco

Keyword(s):

Home Range ◽

Site Fidelity ◽

Home Range Size ◽

Range Size ◽

Caribbean Region ◽

History Of ◽

High Site ◽

Single Night ◽

Exploratory Movements ◽

Moray Eel

AbstractSurprisingly, little is known about basic life history of the largest moray eel species in the Caribbean region, the green moray eel (Gymnothorax funebris). Sixteen eels were captured from the mangrove fringe in multiple bays on St. Croix, USVI, implanted with coded acoustic transmitters, and their movements were tracked for up to 11 months using an array of 37 stationary acoustic receivers. They exhibited high site fidelity in the bays during their residence, using the same general parts of individual bays and did not switch bays except for one individual. There was no relationship between eel size (mean TL = 83 cm, range = 54–126 cm) and home range size (mean area of 95% KUD = 5.8 ha ± 0.7 SE). Most individuals were more frequently detected at night than during the day suggesting greater nocturnal activity. Several of the larger eels (mean TL = 93 cm ± 5.9 SE) showed clear and permanent emigration tracks out of the mangrove estuary to coral reef habitats offshore. For some individuals, these habitat shifts were preceded by exploratory movements away from the eel’s typical home range the night before emigration. All final emigration events took place nocturnally, happened during a single night, and occurred during months from December to May. Mean emigration speed was 3.4 km/h. This study is the first documentation of an ontogenetic habitat shift in moray eels, as well as the first determination of home range size for this species and their site fidelity in mangrove habitats.

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Snowmobile Effects on Movements of White-tailed Deer: A Case-study

Environmental Conservation ◽

10.1017/s0376892900002216 ◽

1979 ◽

Vol 6 (1) ◽

pp. 45-51 ◽

Cited By ~ 16

Author(s):

Ronald G. Eckstein ◽

Thomas F. O'Brien ◽

Orrin J. Rongstad ◽

John G. Bollinger

Keyword(s):

Home Range ◽

Habitat Use ◽

Odocoileus Virginianus ◽

Activity Patterns ◽

Home Range Size ◽

Range Size ◽

Home Ranges

The effects of snowmobile traffic on the winter home-ranges, movements, and activity patterns, of White-tailed Deer (Odocoileus virginianus), were studied during two winters in northern Wisconsin. There were no significant differences in home-range size and habitat use of the Deer in areas with and without snowmobiling. However, snowmobiling caused some Deer to leave the immediate vicinity of the snowmobile trail. Deer were most affected when they were within 61 m of the snowmobile trail.

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The role of the bandwidth matrix in influencing kernel home range estimates for snakes using VHF telemetry data

Wildlife Research ◽

10.1071/wr14233 ◽

2015 ◽

Vol 42 (5) ◽

pp. 437 ◽

Cited By ~ 14

Author(s):

Javan M. Bauder ◽

David R. Breininger ◽

M. Rebecca Bolt ◽

Michael L. Legare ◽

Christopher L. Jenkins ◽

...

Keyword(s):

Home Range ◽

Cross Validation ◽

Radio Telemetry ◽

High Sensitivity ◽

Home Range Size ◽

Range Size ◽

Home Ranges ◽

Telemetry Data ◽

History Of ◽

Sampling Duration

Context Despite the diversity of available home range estimators, no single method performs equally well in all circumstances. It is therefore important to understand how different estimators perform for data collected under diverse conditions. Kernel density estimation is a popular approach for home range estimation. While many studies have evaluated different kernel bandwidth selectors, few studies have compared different formulations of the bandwidth matrix using wildlife telemetry data. Additionally, few studies have compared the performance of kernel bandwidth selectors using VHF radio-telemetry data from small-bodied taxa. Aims In this study, we used eight different combinations of bandwidth selectors and matrices to evaluate their ability to meet several criteria that could be potentially used to select a home range estimator. Methods We used handheld VHF telemetry data from two species of snake displaying non-migratory and migratory movement patterns. We used subsampling to estimate each estimator’s sensitivity to sampling duration and fix rate and compared home range size, the number of disjunct volume contours and the proportion of telemetry fixes not included in those contours among estimators. Key Results We found marked differences among bandwidth selectors with regards to our criteria but comparatively little difference among bandwidth matrices for a given bandwidth selector. Least-squares cross-validation bandwidths exhibited near-universal convergence failure whereas likelihood cross-validation bandwidths showed high sensitivity to sampling duration and fix rate. The reference, plug-in and smoothed cross-validation bandwidths were more robust to variation in sampling intensity, with the former consistently producing the largest estimates of home range size. Conclusions Our study illustrates the performance of multiple kernel bandwidth estimators for estimating home ranges with datasets typical of many small-bodied taxa. The reference and plug-in bandwidths with an unconstrained bandwidth matrix generally had the best performance. However, our study concurs with earlier studies indicating that no single home range estimator performs equally well in all circumstances. Implications Although we did not find strong differences between bandwidth matrices, we encourage the use of unconstrained matrices because of their greater flexibility in smoothing data not parallel to the coordinate axes. We also encourage researchers to select an estimator suited to their study objectives and the life history of their study organism.

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Can the environment influence species home-range size? A case study onCtenomys minutus(Rodentia, Ctenomyidae)

Journal of Zoology ◽

10.1111/jzo.12444 ◽

2017 ◽

Vol 302 (3) ◽

pp. 171-177 ◽

Cited By ~ 5

Author(s):

B. B. Kubiak ◽

D. Galiano ◽

T. R. O. de Freitas

Keyword(s):

Home Range ◽

Home Range Size ◽

Range Size ◽

Environment Influence

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Modeling the relationship between habitat preferences and home-range size: a case study on a large mobile colubrid snake from North America

Journal of Zoology ◽

10.1111/j.1469-7998.2010.00706.x ◽

2010 ◽

Vol 282 (1) ◽

pp. 13-20 ◽

Cited By ~ 24

Author(s):

J. M. Kapfer ◽

C. W. Pekar ◽

D. M. Reineke ◽

J. R. Coggins ◽

R. Hay

Keyword(s):

North America ◽

Home Range ◽

Habitat Preferences ◽

Home Range Size ◽

Range Size ◽

The Relationship

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Home Range and Movement Pattern of a Tailless Black Eagle in Taiwan: A Special Case of Noninvasive Study by Community Science

Journal of Raptor Research ◽

10.3356/jrr-20-107 ◽

2021 ◽

Author(s):

Wen-Horn Lin ◽

Shiao-Yu Hong ◽

Si-Min Lin

Keyword(s):

Home Range ◽

Foraging Behavior ◽

Movement Pattern ◽

Home Range Size ◽

Range Size ◽

Taipei City ◽

Community Science ◽

North And South ◽

Special Case

ABSTRACT A secretive and cautious raptor, the Black Eagle (Ictinaetus malaiensis) is challenging to study. Its highly specialized foraging behavior makes it difficult to capture an individual for tracking. However, a tailless eagle provided an opportunity to describe the home range and movements of one bird for 3 yr from 2013 to 2016. A total of 43 independent photo records were provided by a bird photographers' community. The eagle regularly moved between summering and wintering habitats north and south of Taipei City, Taiwan; home range sizes were estimated as 54.1 and 47.1 km2, respectively. This noninvasive case study provides the first estimates of home range size and movement patterns for the Black Eagle, and highlights the contribution of community science to research on endangered raptors.

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Movement patterns and home range size of tigerfish (Hydrocynus vittatus) in the Incomati River system, South Africa

Koedoe ◽

10.4102/koedoe.v60i1.1397 ◽

2018 ◽

Vol 60 (1) ◽

Cited By ~ 4

Author(s):

Francois Roux ◽

Gert Steyn ◽

Clinton Hay ◽

Ina Wagenaar

Keyword(s):

Life History ◽

Home Range ◽

Large Scale ◽

Specific Activity ◽

Movement Patterns ◽

River System ◽

Home Range Size ◽

Range Size ◽

Management Policy ◽

Fish Movement

Historical data suggested that the tigerfish (Hydrocynus vittatus) of the Incomati River migrates upstream and downstream as part of their life history. It has been suggested that this movement was a prerequisite for successful spawning in inundated floodplains in Mozambique. Recent advances in aquatic radio telemetry provided a reliable mechanism to monitor fish movement and increase knowledge of the ecology of tigerfish. From 04 January 2003 to 22 December 2003, 41 tigerfish in the Incomati River system were fitted with radio transmitters to record movement patterns and estimate home range size. On average, each fish was tracked 72 times, and the total number of fixes was 2971 over the study period, including 1322 summer fixes and 1649 winter fixes. The mean longest distance travelled by tigerfish was 730 m (range = 75 m to 3200 m). The home range size varied between individual fish, but on average fish stayed within a defined home range of 48 846 m2. Tigerfish showed high site fidelity to specific habitats within specific activity zones and movement occurred primarily within these defined zones. Differences in movement pattern, longest distance travelled and home range size could not be attributed to the sex or size of the fish. No large-scale movement patterns associated with specific life history activity were observed; thus, previous reports of large-scale downstream migrations and spawning migrations appear to be invalid. The presence of weirs in the study area impedes free fish movement as these weirs create migration obstructions.Conservation implications: River regulation such as damming, water abstraction, obstructive barriers and channel modification may have a detrimental impact on the survival strategy of this species. Implementation of these results in a management policy will provide a reliable basis for species specific requirements such as upstream reservoir release management; minimum flow volumes required for downstream ecosystem maintenance and management and planning of structures obstructing natural flow.

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Desert kit fox home range – southeastern California

Israel Journal of Ecology and Evolution ◽

10.1080/15659801.2016.1171468 ◽

2015 ◽

Vol 61 (3-4) ◽

pp. 157-161

Author(s):

Charles J. Randel ◽

Nova J. Silvy

Keyword(s):

Life History ◽

Population Density ◽

Home Range ◽

Great Basin ◽

Central Valley ◽

Home Range Size ◽

Range Size ◽

Minimum Convex Polygon ◽

Kit Fox ◽

Open Population

Kit fox (Vulpes macrotis) life history and ecology has been extensively studied in the Great Basin and California's Central Valley, with fewer studies in hot desert regions resulting in regional knowledge gaps. To augment our understanding of kit fox life history and ecology, we conducted a 2-year radio-telemetry study of the desert kit fox (V. m. arsipus) in southeastern California. Fifty-six desert kit foxes were fitted with morality-sensitive radio collars between October 2012 and August 2014 with individuals located five to seven nights per week to determine home range size and population density. Mean home range was 15.77 ± 1.03 km2 (95% fixed kernel) and 18.48 ± 1.77 km2 (minimum convex polygon), and larger than all, but one previous study. We found no difference in home range size based on sex or year. Home range overlaps were significantly larger for mated (79.3% ± 1.35%) than unmated pairs (20.9% ± 1.01%) and consistent with previous studies. Population size was estimated at 88 individuals using open population models, resulting in an estimated density of 0.34/km2 (range 0.26–0.47/km2) which is higher than previously reported. Our study represents the first home range and population density study for desert kit foxes in California and provided critical knowledge of this understudied kit fox population.

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