
James L HaywardAndrews University · Department of Biology
James L Hayward
Ph.D. Washington State Univ
About
109
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Introduction
I am interested in the behavioral ecology of seabirds, bald eagles, and harbor seals. Our research team is funded by grants from the National Science Foundation and Andrews University. At present, I am studying every-other-day ovulation synchrony in gulls as a possible adaptive response to egg cannibalism. I also study the taphonomy of modern eggshell to provide clues regarding the reproductive biology of dinosaurs.
Additional affiliations
July 1986 - present
Position
- Research Professor of Biology
Description
- I study the behavioral ecology of seabirds, bald eagles, and harbor seals. At present, our Seabird Ecology Team is studying ovulation synchrony in gulls in relation to egg cannibalism. Our research is funded by grants from the National Science Foundation.
Publications
Publications (109)
Flightless Cormorants (Phalacrocorax harrisi), the only flightless members of their 27-member genus, are listed as vulnerable on the International Union for Conservation of Nature (IUCN) Red List. The world population of ,1,000 breeding pairs is restricted to scattered small colonies along the coastlines of Isla Fernandina and Isla Isabela, Gala´pa...
Dinosaur eggshell is abundant in the fossil record but only during the last several decades has this reproductive product been considered more than a novelty. Recent work has provided evidence that both whole eggs and fragmented eggshell represent a rich source of information related to palaeoecology and dinosaur reproductive biology. In this paper...
Spontaneous oscillator synchrony is a form of self-organization in which populations of interacting oscillators ultimately cycle together. This phenomenon occurs in a wide range of physical and biological systems. In rats and humans, oestrous/menstrual cycles synchronize through social stimulation with pheromones acting as synchronizing signals. In...
Our purpose in this chapter is to address a significant time-scale discrepancy between the models studied in Chaps. 11 and 12 and the gull populations that motivated them. This discrepancy arises because, unlike in the models, reproductive synchrony and juvenile maturation in gulls occur on different time scales.
In this chapter we apply the differential equation-based modeling techniques developed in Chap. 1 to a marine mammal behavioral system. This research demonstrated that the same modeling techniques developed for bird behavior can be applied more broadly to other organisms. James Hayward, Shandelle Henson, and Brian Dennis, with undergraduate student...
Research reported in this chapter was the initial project carried out by the Seabird Ecology Team. It provided one of the first rigorous demonstrations that a differential equation model using environmental variables can be used to describe, explain, and accurately predict the aggregate behavior of marine vertebrates. It also served as the impetus...
Motivated by the empirical findings in Chaps. 7–9 that egg-laying synchrony is adaptive in the presence of egg cannibalism in gulls, we now extend the proof-of-concept cannibalism model in Chap. 11 to include the possibility of reproductive synchrony.
The study reported in this chapter was carried out in the Galá pagos Islands in parallel with the work on flightless cormorants reported in Chap. 5. Here the application of differential equation modeling to a marine reptilian system further demonstrates the broad applicability of this technique. This work formed the basis of a Master of Science the...
Chapters 1–3 report studies that focus on single state variables within behavioral systems. Behavioral systems, however, involve multiple state variables. In this chapter we demonstrate the efficacy of differential equation-based modeling which focuses on two state variables, behavior and habitat occupancy. This research was initially published in...
Climate change results in a broad range of changes in animals including physiological responses, predator-prey relations, and feeding tactics. In this chapter we explore the impact of changes in sea surface temperature on egg cannibalism, a feeding tactic used by gulls. We use logistic regression and information-theoretic methods of model selection...
In this chapter we use a modification of the classic Lotka-Volterra predator-prey ordinary differential equation model to test whether rebounding bald eagle numbers were primarily responsible for declining numbers of gulls nesting on Protection Island, Washington.
In this chapter we employ logistic regression and Darwinian dynamics to explore how a behavior with a crucial physiological function might be co-opted to function as a coping behavior in response to stress generated by the presence of predators. This study was initially reported in the Journal of Biological Dynamics in 2012 by senior researchers Sh...
A wide variety of natural systems exhibit spontaneous oscillator synchrony. In this chapter we use discrete-time mathematical modeling and Monte Carlo methods to provide the first demonstration of synchronous, every-other-day egg laying in seabirds. Along with Chap. 7, this chapter provides background for empirical and theoretical analyses that app...
This chapter is based on work carried out in the Galápagos Islands, Ecuador in 2011. James Hayward and Susana Velastegui Chávez, with two graduate students, Libby Megna and Brianna Payne, collected the data. Shandelle Henson carried out the data analysis, which involved Poisson regression, logistic regression, and multi-model inference based on the...
In Chap. 7 we described the occurrence of egg cannibalism by gulls, and in Chap. 8 we reported that under certain conditions female gulls lay their eggs on a synchronous, every-other-day schedule. Here we use logistic regression, chi-square analysis, and Monte Carlo simulations to show that every-other-day egg-laying synchrony functions as an adapt...
In this chapter we set up the modeling framework for a study of cannibalism by means of low-dimensional structured population models that distinguish only between cannibals and victims. Our specific interest is on adult cannibalism of juveniles . In Sect. 11.2 we use matrix modeling methodology [5, 7, 8] to develop and analyze a general discrete-ti...
Cannibalism, the killing and eating of conspecifics of any life stage, leads to a variety of behavioral and ecological consequences and is influenced by a range of environmental circumstances among numerous taxa. In birds, cannibalism is particularly well known among gulls. Although multiple studies have linked cannibalism to egg and chick failure...
Increased sea-surface temperatures lead to increased egg cannibalism in Glaucous-winged Gulls (Larus glaucescens). Under these conditions, female gulls, which lay an egg approximately every 2 d, can synchronize egg laying with other females on an every-other-day schedule. Eggs that are laid synchronously are less likely to be cannibalized. The mech...
Sea surface temperatures (SST) in the Pacific Northwest of North America rose 1 C during the last half of the twentieth century. Cannibalism, a behavior observed in diverse taxa, is often associated with low food supplies, which for marine animals can be precipitated by high SSTs. In an 8 year study, we found that in years of higher sea surface tem...
Gulls (Laridae) are primarily diurnal, although many species forage opportunistically at night, and several species copulate at night. We used trail cameras to study time-of-day variation in the rate of copulation by Glaucous-winged Gulls Larus glaucescens in a breeding colony (1500+ pairs) at Protection Island, Washington, USA, from 31 May to 07 J...
Reports on nesting debris generated by great blue heron (Ardea herodias), arboreal nesting birds with ‘semi-altricial’ young, are limited. In this study, surface and subsurface sampling were conducted in 2012 and 2013 in a heronry near the Missouri River in Montana, including bi-weekly collections in 2013 documenting accumulations over the breeding...
• Bald eagle (Haliaeetus leucocephalus) populations in North America rebounded in the latter part of the twentieth century, the result of tightened protection and outlawing of pesticides such as DDT. An unintended consequence of recovery may be a negative impact on seabirds. During the 1980s, few bald eagles disturbed a large glaucous‐winged gull (...
Courtship and copulation constitute crucial elements of avian reproduction and fitness. Despite the potential impact of environmental perturbations and long-term climate change on avian reproduction, few studies provide quantitative information on courtship and copulation behaviors and their responses to proximate environmental factors. We provide...
Reproductive behaviors such as mounting and copulation calls spread through gull breeding colonies via social facilitation. We showed that broadcasts of model copulation calls to breeding Glaucous-winged Gulls (Larus glaucescens) did not increase the overall numbers of bouts of head tossing or mounts, but they did coordinate the timing of subsequen...
We recently reported observations of Common Ravens (Corvus corax) eating eggs, juveniles, and possibly adult Rhinoceros Auklets (Cerorhinca monocerata) on Protection Island National Wildlife Refuge, Jefferson County, Washington. In this new report from 2015, we found 32 eggs presumably eaten by ravens, which represents a 16-fold increase during the...
The effect of sea surface temperature (SST), as a proxy for more general oceanic conditions, on seabird reproduction includes a time lag. In this short communication, we use model-selection techniques to determine the time of year SST should be measured in the Salish Sea in order to best explain the variability in reproductive success the following...
Fraser Darling suggested that reproductive synchrony enhances reproductive success of colonial seabirds as a result of predator satiation. However, the cost of yearly reproductive synchrony is high for colonial species for which intraspecific predation is the primary cause of egg and chick loss. A few studies indicate that egg-laying synchrony on a...
The following article describes the joint research the three authors have conducted for many years at Protection Island, a federally protected National Wildlife Refuge in the Strait of Juan de Fuca in Washington State, and at Galapagos National Park, Ecuador. Their research, which is sponsored by the National Science Foundation, includes a great nu...
Cannibalism, which functions as a life history trait in at least 1300 species of both invertebrates and vertebrates, plays important ecological and evolutionary roles in populations. During times of low resource availability, cannibalism of juveniles by adults can redirect reproductive energy to times of higher resource availability. For example, p...
No abstract is available for this article.
Little is known about oviposition in colonial seabirds. Egg-laying behaviors of Glaucous-winged Gulls (Larus glaucescens) were recorded using custom-modified digital pocket spy cameras. Oviposition involved standing or crouching over the nest, a series of contractions while assuming a characteristic posture, a short labor vocalization at the peak o...
Galápagos marine iguanas (Amblyrhynchus cristatus) forage in marine habitats but spend most of their time hauled out on land. As they move between desert-like terrestrial haul-out sites and temperate-like marine foraging habitats, these ectotherms experience sudden and dramatic temperature differences accommodated primarily through behavioral inste...
Professors Jim Hayward, Shandelle Henson and Jim Cushing form part of an interdisciplinary group of biologists and mathematicians who focus their studies on the behavioural ecology of marine organisms. Here they discuss several aspects of their research and how they enable underrepresented groups to become part of it.
We observed Common Ravens (Corvus corax) on Protection Island, Washington that used their bills to dig into the nesting burrows of Rhinoceros Auklets (Cerorhinca monocerata) and prey on auklet eggs. In addition, we observed a raven fly away from a burrow with an auklet chick, a raven attack and unsuccessful attempt to capture an adult auklet, and a...
We report the flooding and transport of glaucous-winged gull (Larus glaucescens) nests and eggs in response to high tides at a nesting colony in Washington State. Affected nests were located on the beach bordering a small marina. Flooding and transport most commonly occurred during very high tides. Nests with eggs, nests without eggs, and eggs with...
Glaucous-winged gulls Larus glaucescens and western gulls L. occidentalis hybridize extensively where their ranges overlap along the coasts of Washington and Oregon, producing a continuum of phenotypic intergrades between the two parental species. This zone often is considered an example of geographically bounded hybrid superiority, but studies of...
Cannibalism occurs regularly across a broad range of taxa with a variety of ecological and evolutionary consequences. Rises in sea surface temperature (SST) have been linked to increased cannibalism in some species, including polar bears (Ursus maritimus), Peruvian anchovy (Engraulis ringens), and Peruvian hake (Merluccius gayi peruanus), and might...
A 1904 description of the feeding behavior of juvenile Flightless Cormorants suggested that adults feed young by thrusting their beaks with food into the open mouths of young. Other juvenile Pelecaniformes, however, typically feed by reaching into the parent's mouths for food. Using digital photography we found that, contrary to the 1904 descriptio...
Monitoring population trends in harbor seals (Phoca vitulina) generally involves two steps: (i) a census obtained from aerial surveys of haul-out sites, and (ii) an upward correction based on the proportion of seals hauled out as estimated from a sample of telemetry-tagged seals. Here we present a mathematical method for obtaining site-specific cor...
We tested three alternative hypotheses as to the best equation for estimating egg mass from Glaucous-winged Gull egg length and width. The selected allometric model describes 89-94% of the variability in mass. A mathematical model that accurately predicts egg mass from length and width may eliminate the need to use a portable scale during nest surv...
Glaucous-winged Gulls (Larus glaucescens) and Western Gulls (Larus occidentalis) are found along the Pacific Coast of North America. Where their breeding ranges overlap in Oregon and Washington they hybridize, producing a continuum of phenotypic variation. Whereas most colonies containing these hybrids are found on islands along the coast, several,...
Protection Island, Washington, is one of the most important nesting sites for Glaucous-winged Gulls (Larus glaucescens) in the Puget Sound area. Changes in the numbers and distribution of nests in a Glaucous-winged Gull colony on Violet Point, Protection Island, were tracked from 1980 to 2010. The colony grew steadily until the early 1990s, then de...
In humans, coping behaviour is an action taken to soothe oneself during or after a stressful or threatening situation. Some human behaviours with physiological functions also serve as coping behaviours, for example, comfort sucking in infants and comfort eating in adults. In birds, the behaviour of preening, which has important physiological functi...
The taphonomic effects of heat and or fire on bones, conodonts, and plant tissues have received much attention from paleontologists and geologists, but the effect of high temperatures on amniote eggshell has been unknown. We compared the effects of heat on extant avian eggshell, which is constructed primarily of CaCO3 deposited within a protein mat...
Mathematical ecology has attracted a vibrant community of applied mathematicians in recent decades. Applications to actual biological systems and collaborations with biologists are encouraged within the community and have become more common. A variety of nonlinear phenomena have been modeled successfully in several laboratory systems. Nevertheless,...
Spontaneous oscillator synchrony has been documented in a wide variety of electrical, mechanical, chemical, and biological systems, including the menstrual cycles of women and estrous cycles of Norway Rats (Rattus norvegicus). In temperate regions, many colonial birds breed seasonally in a time window set by photoperiod; some studies have suggested...
From 1980 to 1998, Washington's Bald Eagle (Haliaeetus leucocephalus) population increased at an annual rate of 10%. Over the same time period, foraging activity of Bald Eagles at marine bird breeding colonies also increased. From 1993 to 2008, we observed foraging-related behavior of Bald Eagles on Violet Point, Protection Island. This island host...
Abstract Gulls are highly adaptable animals that thrive in proximity to humans. Although gulls enjoy legal protection in North America, England, and Europe, they often conflict with human interests by spreading disease, transporting contaminants, fouling public areas with droppings, and colliding with aircraft. Of particular concern are aggregates...
Las aves marinas se mueven a lo largo del día a través de ambientes cambiantes y distribuidos en parches conforme realizan diferentes comportamientos. Nosotros estudiamos la dinámica de la abundancia diurna de gaviotas Larus glaucescens en un parche de hábitat dedicado al descanso en el estrecho de Juan de Fuca, Washington. Construimos tres modelos...
Dinosaurs, like modern birds, produced enormous quantities of eggshell as part of the reproductive process. Sometimes this eggshell was fossilized but most commonly was destroyed by weathering. The degree to which bacteria may have contributed to this weathering process has not been explored. In this study, fresh glaucous-winged gull (Larus glauces...
Development of locomotor activity is crucial in tetrapods. In birds, this development leads to different functions for hindlimbs and forelimbs. The emergence of walking and flying as very different complex behavior patterns only weeks after hatching provides an interesting case study in animal development. We measured the diaphyseal lengths and mid...
We constructed differential equation models for the diurnal abundance and distribution of breeding glaucous-winged gulls (Larus glaucescens) as they moved among nesting and non-nesting habitat patches. We used time scale techniques to reduce the differential equations to algebraic equations and connected the models to field data. The models explain...
Protection Island National Wildlife Refuge, WA, is home to the majority of breeding seabirds and harbor seals found in the Puget Sound/San Juan Island area. The island consists of a high central plateau flanked by bluffs on the north and south and by low points on the southwest and east. We analyzed the physical and vegetational changes in Protecti...
This article is a species account for glaucous-winged gulls (Larus glaucescens), a common gull of the Pacific Northwest coast of North America.
Many species show considerable variation in behaviour among individuals. We show that some behaviours are largely deterministic and predictable with mathematical models. We propose a general differential equation model of behaviour in field populations and use the methodology to explain and predict the dynamics of sleep and colony attendance in sea...
In previous studies we developed a general compartmental methodology for modeling animal behavior and applied the methodology to marine birds and mammals. In this study we used the methodology to construct a system of two differential equations to model the dynamics of territory attendance and preening in a gull colony on Protection Island, Strait...
Marine birds and mammals move between various habitats during the day as they engage in behaviors related to resting, sleeping, preening, feeding, and breeding. The per capita rates of movement between these habitats, and hence the habitat occupancy dynamics, often are functions of environmental variables such as tide height, solar elevation, wind...
Diurnal habitat occupancy dynamics of Glaucous-winged Gulls were evaluated in a system of six habitats on and around Protection Island, Washington. Data were collected on the rates of gull movement between habitat patches, and from these data the probabilities of transitions between habitats were estimated as functions of tide height and time of da...
The diurnal distribution and abundance dynamics of loafing Glaucous-winged Gulls (Larus glaucescens) were examined at Protection Island National Wildlife Refuge, Strait of Juan de Fuca, Washington. Asynchronous movement of gulls among three habitat patches dedicated to loafing was modeled as a function of environmental variables using differential...
It was once assumed that commercially important fish make up significant portions of seal diets. As a consequence, prior to the 1970s many seal populations were dramatically reduced by rampant slaughtering. Today, seals and other marine mammals are valued components of marine ecosystems and their numbers are carefully managed. To facilitate managem...
The mode of departure of Rhinoceros Auklet fledglings from their nest burrows has remained uncertain. Both walk-down and fly-down hypotheses have been proposed. Here we use the unique geography of Protection Island, Washington, to evaluate the fly-down hypothesis. Some fledglings raised on Protection Island do appear to walk to the water, but our r...
Avian and non-avian dinosaur eggshell contains clues that are helpful in the reconstruction of ancient habitats and behaviors. Fossilized eggshell often shows signs of corrosion attributed to acid dissolution of the calcium carbonate, but this process has never been quantified in controlled experiments. In work reported here, extant avian dinosaur...
Seabirds move throughout the day in changing, patchy environments as they engage in various behaviors. We studied the diurnal abundance dynamics of Glaucous-winged Gulls (Larus glaucescens) in a habitat patch dedicated to loafing in the Strait of Juan de Fuca, Washington. We constructed three differential equation models as alternative hypotheses a...
Seabirds move throughout the day in changing, patchy environments as they engage in various behaviors. We studied the diurnal abundance dynamics of Glaucous-winged Gulls (Larus glaucescens) in a habitat patch dedicated to loafing in the Strait of Juan de Fuca, Washington. We constructed three differential equation models as alternative hypotheses a...
This is the second report of sexual aggression exhibited by an adult northern elephant seal on harbor seal pups.
Here I report two cases of common garter snake (Thamnophis sirtalis) predation on ring-billed gull (Larus delawarensis) chicks at Harper Island, Sprague Lake, Adams County, Washington.
Given recent increases in numbers of bald eagles throughout North America and their potential impact on concentrations of breeding birds and mammals, we describe temporal and spatial patterns of flight activity and feeding behavior of bald eagles at Protection Island National Wildlife Refuge, Washington.
Eggshell taphonomy often is acknowledged to be worthy of investigation, but few studies have examined factors influencing eggshell preservation. In this study eggshell weathering, fragmentation, dispersal, orientation, and predation were characterized in field and laboratory studies. Modern gull eggshell fragment dispersal and orientation patterns...
Experiments to identify taphonomic variables influencing the fossilization of eggs and eggshells in marine environments were carried out using chicken eggs as models. We examined: (1) the recruitment of eggs into the seal by wave and tidal action; (2) the transport of eggshell fragments by simulated turbidity currents; (3) the capacities of whole e...
“I spent the first thirty years of my life learning to be a scientist, and the next twenty-five years of my life trying to become a humanist and an artist." Paul Johnsgard immerses himself in several worlds, but for the eclectic teacher, writer, artist, and scientist, these worlds merge in a burst of feathered movement, color, and shape. Johnsgard...
Nest-site selection and reproductive success are reported for ring-billed gulls nesting at Sprague Lake, Washington, in 1981. Gulls nesting in tall grass and rocky beach habitats began laying significantly earlier than other gulls. Incubation times also varied by location, with birds in peripheral areas spending over three days longer to incubate t...
Great horned owls usually prey on a variety of small- to medium-sized mammals and birds, with mammals forming the bulk of their diets. However, great horned owls living on Protection Island, Jefferson Co., Washington, are noteworthy in that their regurgitated pellets contain bird remains exclusively. Here we characterize these unusual pellets and t...
Eggshells of ring-billed gulls buried by Mount St. Helens ash at an eastern Washington colony were excavated one and seven years following the ashfall. These were compared to unburied eggshells using scanning electron microscopy, polarized light microscopy, electron probe microanalysis, and cathodoluminescence microscopy. Physical dissolution of th...
Ashfall from Mount St. Helens' May 18, 1980 eruption covered eggs and nests of two species of colonial, ground-nesting gulls. While some members of both species excavated their eggs from beneath the ash, most eggs and nests remained buried. One year after the ashfall, habitats known to contain pre-ashfall nests were transected and the ash layer was...
The early history of paleontology is replete with examples of misidentifications of fossils. Teeth and bones of mastodons and mammoths were especially apt to be identified as the remains of antediluvian giants. These fallacies were entertained not only by the uninformed, but also by the intellectual elite. Even today misidentified fossils are somet...
Studied a nesting colony of ring-billed (
Larus delawarensis) and California (
L. californicus) gulls at Sprague Lake, Washington. Both species left their nests unattended during the ashfall. Using both their feet and bills, significantly more California than ring-billed gulls excavated their ash-covered nests. Of the Ss not excavating, few Califor...
On 18 May 1980, volcanic ash buried nests and eggs of ring-billed and California (Larus delawarensis and L. californicus) breeding on Harper Island, Sprague Lake, Washington, 330 km ENE of erupting Mount St. Helens. This paper describes the effects of the ash on the colony and species-specific responses to the ash that substantially lessened the im...
This paper describes a simple technique for marking eggs during studies of reproductive success in gulls.
Typescript. Thesis (Ph. D.)--Washington State University, 1982. Includes bibliographical references (leaves 53-58).