James C. Ha

Social and ecological factors influencing vigilance by northwestern crows, Corvus caurinus

Vigilance behaviour is thought to be largely controlled by the threat of predation on foragers. In addition, an inverse relationship between group size and vigilance has been documented repeatedly and is known as the group size effect. We suggest that groups of beach-foraging northwestern crows are vigilant for predators and for opportunities to steal (‘scrounge’) from conspecifics. We collected data using 5-min focal samples that recorded search time, scanning frequency and bout lengths, predator presence, prey type and theft. We also recorded group size, time of day, temperature, and tide height and direction, resulting in 2950 foraging trials. Results indicated that increased scanning during a trial predicted trials that would end in theft. Group size did not significantly influence the proportion of scanning in a trial, but scan bout length increased with increasing group size. This result is opposite to that predicted by the group size effect and suggests that more birds means more opportunities to scrounge or be scrounged upon. This rejection of the group size effect is most likely due to the trade-offs between group size and scrounging opportunities.

Impacts of acute and long‐term vehicle exposure on physiology and reproductive success of the northern spotted owl

Stress physiologists posit that multiple simultaneous demands faced by an organism may have non-additive effects on the magnitude of their response to disturbance. The environmental assessment literature emphasizes a similar phenomenon at the population level, arguing that populations can compensate for perturbations up to a threshold, beyond which disturbance impacts may be greatly magnified—and even cause system collapse. We integrated these two approaches to examine the roles of environment, life history stage, prior disturbance experience, and their interactions on vulnerability to disturbance in a free-living species. Specifically, we examined the effects of off-highway vehicle use on the federally threatened northern spotted owl (NSO), Strix occidentalis caurina, by measuring fecal glucocorticoid metabolites (fGCs), which reflect disturbance; fecal thyroid hormone metabolites (fT3), which reflect nutrition; and the number of offspring fledged within a season. We experimentally applied one hour of mo...

The Effects of Visitor Density and Intensity on the Behavior of Two Captive Jaguars (Panthera onca)

Several researchers have reported significant effects of visitor density and intensity on captive animal behavior. This study determined whether this was the case for 2 captive jaguars housed at the Woodland Park Zoo, Seattle, WA. Subjects were monitored for changes in behavior as a function of visitor density and intensity. The jaguars were observed for 8 hr per week for 29 weeks—March 31 until October 11, 1998—for a total of 230 hr. Continuous frequency sampling was used, and visitor density and intensity were recorded every minute. Parametric statistics were used to test for correlations between behavior and density, intensity, or a combination of the two. Both density and intensity were significant for time spent non-visible for both cats, and intensity showed a significant effect on the females pacing behavior. In addition, the male cat exhibited a trend for increased aggression based on both visitor density and intensity and a trend of intensity affecting his social behavior. In conclusion, both density and intensity had a significant effect on behavior, with intensity showing a larger effect.

Effects of ecology and prey characteristics on the use of alternative social foraging tactics in crows, Corvus caurinus

The producer–scrounger model assumes that producers are animals that search for food, and scroungers are animals that steal food found by producers. By following foraging decisions made by beach-foraging crows, we assessed individual variability in strategy use, variables influencing the finder’s share (when defined as the probability of retaining a prey item in the presence of food theft behaviour) and the benefits and costs of producing and scrounging. Data were collected using focal and all-occurrences scan sampling. Results indicated that more individuals were likely to use both producing and scrounging tactics than to be ‘pure’ producers. No pure scroungers were documented. When producers obtained scroungeable items, scroungers attempted to steal the item 46% of the time. Forty-one per cent of attempted scrounges were successful. Thus, producers suffered a 19% loss rate of scroungeable items to scroungers, although producers had access to large numbers of small (nonscroungeable) items. Although there were significantly more scroungeable prey items available at lower tides, there was no significant relationship between prey density and scrounge attempts or actual thefts. No ecological factors (group size, temperature, time of day, season) or individual characteristics (age, sex) influenced the probability of retaining prey. Prey retention was determined only by characteristics of the prey items: larger prey items or those with longer handling times were most likely to be stolen.  2003 Published by Elsevier Ltd on behalf of The Association for the Study of Animal Behaviour.

Behavioral measurement of temperament in male nursery-raised infant macaques and baboons

We define temperament as an individuals set of characteristic behavioral responses to novel or challenging stimuli. This study adapted a temperament scale used with rhesus macaques by Schneider and colleagues [American Journal of Primatology 25:137–155, 1991] for use with male pigtailed macaque (Macaca nemestrina, n = 7), longtailed macaque (M. Fascicularis, n = 3), and baboon infants (Papio cynocephalus anubis, n = 4). Subjects were evaluated twice weekly for the first 5 months of age during routine removal from their cages for weighing. Behavioral measures were based on the subjects interactions with a familiar human caretaker and included predominant state before capture, response to capture, contact latency, resistance to testers hold, degree of clinging, attention to environment, defecation/urination, consolability, facial expression, vocalizations, and irritability. Species differences indicated that baboons were more active than macaques in establishing or terminating contact with the tester. Temperament scores decreased over time for the variables Response to Capture and Contact Latency, indicating that as they grew older, subjects became less reactive and more bold in their interactions with the tester. Temperament scores changed slowly with age, with greater change occurring at younger ages. The retention of variability in reactivity between and within species may be advantageous for primates, reflecting the flexibility necessary to survive in a changing environment. Am. J. Primatol. 47:43–50, 1999.

ONTOGENY OF HUMAN BRAIN DOPAMINE RECEPTORS. I. DIFFERENTIAL EXPRESSION OF 3H-SCH23390 AND 3H-YM09151-2 SPECIFIC BINDING

Dopamine receptor expression in human fetal forebrain (between 6 and 20 weeks of gestation) was measured using tissue-slice receptor autoradiography with the D1-like and D2-like antagonists [3H]-SCH23390 and [3H]-YM09151-2, respectively. Tissue sections were assayed in saturation studies and examined for age- and sex-related changes in Bmax. We made the following observations: (1) the ages at which D1- and D2-like receptors were first expressed in whole forebrain sections could be reliably identified but were not significantly different from one another (gestational age 65 days for D1- vs. 72 days for D2-like receptors); (2) age-related increases in both D1- and D2-like receptors were demonstrated in forebrain and, from the middle of the first to the middle of the second trimester, the Bmax for each ligand increased by an order of magnitude after the onset of the specific binding sites expression; (3) age-related increases in D1-like receptors, but not D2-like receptors, could be demonstrated in cortex; and, (4) in one case of trisomy 18, the Bmax for [3H]-SCH23390 was significantly elevated above the 95% confidence interval when compared to an age-regressed normal sample. Although D2-like receptor density significantly increased with age in forebrain, age-regressed changes in D2-like receptor expression in cortex and striatum did not reach statistical significance. Likewise, a comparison of the mean Bmaxs by sex for both ligands in midgestational striatum failed to reach significance. These data corroborate the findings of other investigators who have delineated the ontogeny of dopaminergic systems in other animal species. The regional differences in the expression of dopamine receptor families may be relevant to the role which dopamine may play during normal gestational brain development. Moreover, significant deviations in dopamine receptor expression during gestation (as seen in this one case of trisomy 18) may signify underlying pathological processes that ultimately are manifested by abnormal psychological development and/or cognitive functioning.

Social housing and pregnancy outcome in captive pigtailed macaques

We present a retrospective analysis of 30 years of breeding records from a colony of pigtailed macaques at the University of Washingtons Regional Primate Research Center, specifically examining the effects on pregnancy outcome of sire presence, presence of other pregnant females, group stability, overall group size, and dam age and parity. Data on 2,040 pregnancies (1,890 live births) of socially housed pigtailed macaques (Macaca nemestrina) were obtained from the Washington Regional Primate Research Centers animal colony records from 1967 to 1996. Our results suggest that the presence of the sire and other pregnant females, fewer moves, and lower parity increases the probability of a viable birth. In viable and nonviable births, gestation length was positively related to contact with the sire and other pregnant females, number of moves, and dam age. Once the effect of gestational age was taken into account, birthweight increased with increasing parity and decreased with dam age. Clinical treatment of the dam decreased as sire presence and group size increased and number of moves decreased. The length of treatment was dependent on the number of moves experienced by the dam, with more moves associated with longer treatments. Sire presence was the single most important factor in nearly all measures of reproductive outcome. Am. J. Primatol. 47:153–163, 1999.

Resources for genetic management and genomics research on non-human primates at the National Primate Research Centers (NPRCs)

Abstract The National Primate Research Centers (NPRCs) established Working Groups (WGs) for developing resources and mechanisms to facilitate collaborations among non‐human primate (NHP) researchers. Here we report the progress of the Genome Banking and the Genetics and Genomics WGs in developing resources to advance the exchange, analysis and comparison of NHP genetic and genomic data across the NPRCs.

Developmental and Cross-Situational Stability in Infant Pigtailed Macaque Temperament

We assessed developmental stability and context generalizability of temperament in pigtailed macaques (Macaca nemestrina) from the University of Washington Infant Primate Research Lab. A principal components analysis condensed 6 behavioral measures into 2 components, interpreted as reactivity and boldness. Changes in these measures over the 1st 10 months of development showed a trend toward calmer and bolder behavior with age, with significant individual variation in the pattern of change. Boldness showed a quadratic pattern of change, whereas reactivity decreased linearly. We also studied the relationship between temperament and response to a novelty probe. The magnitude of the response to the novelty probe decreased slightly over time, and boldness and reactivity in a familiar setting did not predict these changes in response to novelty. In a 2nd principal components analysis, reactivity to novelty represented a distinct aspect of temperament. Our results demonstrate developmental changes and context dependency in macaque behavior.

Temperament in rhesus, long-tailed, and pigtailed macaques varies by species and sex

Temperament differs among individuals both within and between species. Evidence suggests that differences in temperament of group members may parallel differences in social behavior among groups or between species. Here, we compared temperament between three closely related species of monkey—rhesus (Macaca mulatta), long‐tailed (M. fascicularis), and pigtailed (M. nemestrina) macaques—using cage‐front behavioral observations of individually housed monkeys at a National Primate Research Center. Frequencies of 12 behaviors in 899 subjects were analyzed using a principal components analysis to identify temperament components. The analysis identified four components, which we interpreted as Sociability toward humans, Cautiousness, Aggressiveness, and Fearfulness. Species and sexes differed in their average scores on these components, even after controlling for differences in age and early‐life experiences. Our results suggest that rhesus macaques are especially aggressive and unsociable toward humans, long‐tailed macaques are more cautious and fearful, and pigtailed macaques are more sociable toward humans and less aggressive than the other species. Pigtailed males were notably more sociable than any other group. The differences observed are consistent with reported variation in these species’ social behaviors, as rhesus macaques generally engage in more social aggression and pigtailed macaques engage in more male–male affiliative behaviors. Differences in predation risks are among the socioecological factors that might make these species‐typical behaviors adaptive. Our results suggest that adaptive species‐level social differences may be encoded in individual‐level temperaments, which are manifested even outside of a social context. Am. J. Primatol. 75:303‐313, 2013.