Apparent survival and cost of reproduction for White-lined Tanager (Tachyphonus rufus, Thraupidae) in the northern Atlantic Rainforest, Brazil.

Understanding latitudinal variation in avian life-history traits has been a focus of many demographic studies around the world. However, we still know little about annual or intra-annual demographic variation within tropical regions or about how factors such as breeding season and precipitation influence demographic rates. In this study, we estimated intra-annual apparent survival of the White-lined Tanager (Tachyphonus rufus) using capture-mark-recapture data from northeastern Brazil. We tested whether survival varied seasonally (breeding vs. non-breeding), with rainfall, by age and residence status in our study area. Intra-annual apparent survival was correlated with the reproductive cycle, being lower during the breeding (0.65 ± 0.16 SE) vs. the non-breeding season (0.97 ± 0.05 SE). The annual apparent survival (~0.6) was relatively low for a tropical species. In both years, we observed highest abundance in spring (November, 3.1-3.7 birds/ha) and lowest abundance in autumn-winter periods (May-August, 1.1-1.4 bird/ha). The low survival during the breeding season probably reflects the trade-off between survival and reproduction and the cost of reproduction. Our findings represent an advance in the understanding of the demography of tropical birds because we did not find a predicted high annual apparent survival, and we elucidated some aspects of intra-annual variation in survival. Further exploration of latitudinal variation in demographic traits, especially in diverse, but poorly known habitats is needed to fully vet and develop life history theories

Apparent survival and cost of reproduction for White-lined Tanager (<i>Tachyphonus rufus</i>, Thraupidae) in the northern Atlantic Rainforest, Brazil

<div><p>Understanding latitudinal variation in avian life-history traits has been a focus of many demographic studies around the world. However, we still know little about annual or intra-annual demographic variation within tropical regions or about how factors such as breeding season and precipitation influence demographic rates. In this study, we estimated intra-annual apparent survival of the White-lined Tanager (<i>Tachyphonus rufus</i>) using capture-mark-recapture data from northeastern Brazil. We tested whether survival varied seasonally (breeding vs. non-breeding), with rainfall, by age and residence status in our study area. Intra-annual apparent survival was correlated with the reproductive cycle, being lower during the breeding (0.65 ± 0.16 SE) vs. the non-breeding season (0.97 ± 0.05 SE). The annual apparent survival (~0.6) was relatively low for a tropical species. In both years, we observed highest abundance in spring (November, 3.1–3.7 birds/ha) and lowest abundance in autumn-winter periods (May-August, 1.1–1.4 bird/ha). The low survival during the breeding season probably reflects the trade-off between survival and reproduction and the cost of reproduction. Our findings represent an advance in the understanding of the demography of tropical birds because we did not find a predicted high annual apparent survival, and we elucidated some aspects of intra-annual variation in survival. Further exploration of latitudinal variation in demographic traits, especially in diverse, but poorly known habitats is needed to fully vet and develop life history theories.</p></div

Estimates of intra-annual apparent survival based on Huggins robust design models for the White-lined Tanager (<i>T</i>. <i>rufus</i>) in northeastern Brazil.

<p>Estimates of intra-annual apparent survival based on Huggins robust design models for the White-lined Tanager (<i>T</i>. <i>rufus</i>) in northeastern Brazil.</p

Average annual estimates of apparent survival (Φ; mean ± SD) and the maximum and minimum values estimated for Neotropical birds.

<p>Average annual estimates of apparent survival (Φ; mean ± SD) and the maximum and minimum values estimated for Neotropical birds.</p

Top nine Huggins robust design models for a population of White-lined Tanager (<i>T</i>. <i>rufus</i>) in northeastern Brazil.

<p>These nine represent 99% of the weight in the entire model set. The global model and the constant model (23^rd and 61^st ranked model in the set respectively) are shown for comparison.</p

Intra-annual estimates of abundance (mean ± SE) for the White-lined Tanager (<i>T</i>. <i>rufus</i>) in a 12 ha surveyed area of northeastern Brazil based on Huggins robust design models and conditional on birds being first captured on the study site.

<p>Intra-annual estimates of abundance (mean ± SE) for the White-lined Tanager (<i>T</i>. <i>rufus</i>) in a 12 ha surveyed area of northeastern Brazil based on Huggins robust design models and conditional on birds being first captured on the study site.</p

Model-averaged estimates of capture (<i>p</i>) and recapture (<i>c</i>) based on Huggins robust design models for the White-lined Tanager (<i>T</i>. <i>rufus</i>) in northeastern Brazil.

<p>The vertical bars represent standard error estimates.</p

Encounter histories.txt

This file contains the capture-recapture encounter histories of the White-lined Tanager <i>Tachyphonus rufus</i>, a Neotropical passerine bird. It follows a robust design structure and presents 32 occasions (four occasions x eight primary sessions). With this data set is possible to create and reproduce all design models contained in our article. <br><sup></sup