Egg temperature and initial brood patch area determine hatching asynchrony in Magellanic penguinSpheniscus magellanicus

Melina Barrionuevo; Esteban Frere

doi:10.1111/jav.00662

Ecological and Physiological Factors Affecting Brood Patch Area and Prolactin Levels in Arctic-Nesting Geese

The Auk ◽

10.1093/auk/123.2.405 ◽

2006 ◽

Vol 123 (2) ◽

pp. 405-418 ◽

Cited By ~ 3

Author(s):

Jón Einar Jónsson ◽

Alan D. Afton ◽

Ray T. Alisauskas ◽

Cynthia K. Bluhm ◽

Mohamed E. El Halawani

Keyword(s):

Body Condition ◽

The Body ◽

Nest Size ◽

Patch Area ◽

Physiological Factors ◽

Factors Affecting ◽

Chen Caerulescens ◽

Brood Patch ◽

Snow Geese ◽

Ross's Geese

AbstractWe investigated effects of ecological and physiological factors on brood patch area and prolactin levels in free-ranging Lesser Snow Geese (Chen caerulescens caerulescens; hereafter “Snow Geese”) and Ross's Geese (C. rossii). On the basis of the body-size hypothesis, we predicted that the relationships between prolactin levels, brood patch area, and body condition would be stronger in Ross's Geese than in the larger Snow Geese. We found that brood patch area was positively related to clutch volume and inversely related to prolactin levels in Ross's Geese, but not in Snow Geese. Nest size, nest habitat, and first egg date did not affect brood patch area in either species. Prolactin levels increased as incubation progressed in female Snow Geese, but this relationship was not significant in Ross's Geese. Prolactin levels and body condition (as indexed by size-adjusted body mass) were inversely related in Ross's Geese, but not in Snow Geese. Our findings are consistent with the prediction that relationships between prolactin levels, brood patch area, and body condition are relatively stronger in Ross's Geese, because they mobilize endogenous reserves at faster rates than Snow Geese.Factores Ecológicos y Fisiológicos que Afectan el Área del Parche de Incubación y los Niveles de Prolactina en Gansos Nidificantes del Ártico

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EFFECTS OF OVARIAN STEROIDS AND PROLACTIN ON THE SEQUENTIAL DEVELOPMENT OF NESTING BEHAVIOUR IN FEMALE BUDGERIGARS

Journal of Endocrinology ◽

10.1677/joe.0.0670029 ◽

1975 ◽

Vol 67 (1) ◽

pp. 29-39 ◽

Cited By ~ 27

Author(s):

R. E. HUTCHISON

Keyword(s):

Initial Phase ◽

Treated Group ◽

Egg Laying ◽

Patch Area ◽

Ovarian Steroids ◽

Brood Patch ◽

Sequential Development ◽

Incubation Behaviour ◽

Nesting Behaviour ◽

Precocious Development

SUMMARY As intact, breeding female budgerigars approach egg-laying, they spend an increasing amount of time in the nestbox and nest hollow. The brood patch area begins to defeather and becomes vascular and the oviduct increases in weight. Precursory albumen forms in the tubular glands of the oviduct. Oestradiol (OB) treatment in combination with prolactin (OB + PL) induced ovariectomized budgerigars to display nesting behaviour which did not differ from that shown by intact females in the 3 days immediately preceding egg-laying. In contrast, OB induced only the initial phase of the nesting sequence and the effects of OB in combination with progesterone (OB + PR) were intermediate between treatments with OB alone and OB + PL. Incubation of artificial eggs occurred only in the OB + PL group and the latency to display of the incubation posture was shorter in the OB + PL group than in the OB + PR group. No incubation posture was displayed by the OB-treated group. Oviduct development was not influenced by prolactin, but progesterone induced precocious development of tubular glands in the magnum region of the oviduct. Treatment with OB + PR induced uniform development of precursor albumen in the tubular glands. Development of the brood patch occurred with both OB + PL and OB + PR treatment. However, OB + PR resulted in defeathering which was advanced in relation to vascularity when compared with intact breeding females, whereas defeathering and vascularity of the OB + PL group did not differ from that of intact females at egg-laying. These results indicate that prolactin in combination with oestradiol was more effective than progesterone not only in inducing the later phases of nesting behaviour but also in initiating incubation behaviour and defeathering of the brood patch area.

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ECOLOGICAL AND PHYSIOLOGICAL FACTORS AFFECTING BROOD PATCH AREA AND PROLACTIN LEVELS IN ARCTIC-NESTING GEESE

The Auk ◽

10.1642/0004-8038(2006)123[405:eapfab]2.0.co;2 ◽

2006 ◽

Vol 123 (2) ◽

pp. 405 ◽

Cited By ~ 10

Author(s):

Jón Einar Jónsson ◽

Alan D. Afton ◽

Ray T. Alisauskas ◽

Cynthia K. Bluhm ◽

Mohamed E. El Halawani

Keyword(s):

Patch Area ◽

Physiological Factors ◽

Factors Affecting ◽

Brood Patch

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Optimal Hatching Asynchrony in Birds: Comments on Richter's Critique of Clark and Wilson's Model

The American Naturalist ◽

10.1086/284401 ◽

1985 ◽

Vol 126 (1) ◽

pp. 123-128 ◽

Cited By ~ 2

Keyword(s):

Hatching Asynchrony

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Using Bayesian Belief Networks to assess the influence of landscape connectivity on ecosystem service trade-offs and synergies in urban landscapes in the UK

Landscape Ecology ◽

10.1007/s10980-021-01307-6 ◽

2021 ◽

Author(s):

James D. Karimi ◽

Jim A. Harris ◽

Ron Corstanje

Keyword(s):

Functional Connectivity ◽

Ecosystem Service ◽

Urban Areas ◽

Landscape Connectivity ◽

Structural Characteristics ◽

Bird Species ◽

Bayesian Belief Networks ◽

Belief Networks ◽

Patch Area ◽

Trade Offs

Abstract Context Landscape connectivity is assumed to influence ecosystem service (ES) trade-offs and synergies. However, empirical studies of the effect of landscape connectivity on ES trade-offs and synergies are limited, especially in urban areas where the interactions between patterns and processes are complex. Objectives The objectives of this study were to use a Bayesian Belief Network approach to (1) assess whether functional connectivity drives ES trade-offs and synergies in urban areas and (2) assess the influence of connectivity on the supply of ESs. Methods We used circuit theory to model urban bird flow of P. major and C. caeruleus at a 2 m spatial resolution in Bedford, Luton and Milton Keynes, UK, and Bayesian Belief Networks (BBNs) to assess the sensitivity of ES trade-offs and synergies model outputs to landscape and patch structural characteristics (patch area, connectivity and bird species abundance). Results We found that functional connectivity was the most influential variable in determining two of three ES trade-offs and synergies. Patch area and connectivity exerted a strong influence on ES trade-offs and synergies. Low patch area and low to moderately low connectivity were associated with high levels of ES trade-offs and synergies. Conclusions This study demonstrates that landscape connectivity is an influential determinant of ES trade-offs and synergies and supports the conviction that larger and better-connected habitat patches increase ES provision. A BBN approach is proposed as a feasible method of ES trade-off and synergy prediction in complex landscapes. Our findings can prove to be informative for urban ES management.

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Heat/mass transport in shear flow over a heterogeneous surface with first-order surface-reactive domains

Journal of Fluid Mechanics ◽

10.1017/jfm.2015.528 ◽

2015 ◽

Vol 782 ◽

pp. 260-299 ◽

Cited By ~ 8

Author(s):

Preyas N. Shah ◽

Eric S. G. Shaqfeh

Keyword(s):

Mass Transfer ◽

Shear Rate ◽

Shear Flow ◽

Reaction Rate ◽

Patch Size ◽

Patch Area ◽

First Order ◽

Effective Boundary ◽

Order Surface ◽

Slip Distance

Surfaces that include heterogeneous mass transfer at the microscale are ubiquitous in nature and engineering. Many such media are modelled via an effective surface reaction rate or mass transfer coefficient employing the conventional ansatz of kinetically limited transport at the microscale. However, this assumption is not always valid, particularly when there is strong flow. We are interested in modelling reactive and/or porous surfaces that occur in systems where the effective Damköhler number at the microscale can be $O(1)$ and the local Péclet number may be large. In order to expand the range of the effective mass transfer surface coefficient, we study transport from a uniform bath of species in an unbounded shear flow over a flat surface. This surface has a heterogeneous distribution of first-order surface-reactive circular patches (or pores). To understand the physics at the length scale of the patch size, we first analyse the flux to a single reactive patch. We use both analytic and boundary element simulations for this purpose. The shear flow induces a 3-D concentration wake structure downstream of the patch. When two patches are aligned in the shear direction, the wakes interact to reduce the per patch flux compared with the single-patch case. Having determined the length scale of the interaction between two patches, we study the transport to a periodic and disordered distribution of patches again using analytic and boundary integral techniques. We obtain, up to non-dilute patch area fraction, an effective boundary condition for the transport to the patches that depends on the local mass transfer coefficient (or reaction rate) and shear rate. We demonstrate that this boundary condition replaces the details of the heterogeneous surfaces at a wall-normal effective slip distance also determined for non-dilute patch area fractions. The slip distance again depends on the shear rate, and weakly on the reaction rate, and scales with the patch size. These effective boundary conditions can be used directly in large-scale physics simulations as long as the local shear rate, reaction rate and patch area fraction are known.

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