Naive poison frog tadpoles use bi-modal cues to avoid insect predators but not heterospecific predatory tadpoles

For animals to survive until reproduction, it is crucial that juveniles successfully detect potential predators and respond with appropriate behavior. The recognition of cues originating from predators can be innate or learned. Cues of various modalities might be used alone or in multi-modal combinations to detect and distinguish predators but studies investigating multi-modal integration in predator avoidance are scarce. Here, we used wild, naive tadpoles of the Neotropical poison frog Allobates femoralis ( Boulenger, 1884) to test their reaction to cues with two modalities from two different sympatrically occurring potential predators: heterospecific predatory Dendrobates tinctorius tadpoles and dragonfly larvae. We presented A. femoralis tadpoles with olfactory or visual cues, or a combination of the two, and compared their reaction to a water control in a between-individual design. In our trials, A. femoralis tadpoles reacted to multi-modal stimuli (a combination of visual and chemical information) originating from dragonfly larvae with avoidance but showed no reaction to uni-modal cues or cues from heterospecific tadpoles. In addition, visual cues from conspecifics increased swimming activity while cues from predators had no effect on tadpole activity. Our results show that A. femoralis tadpoles can innately recognize some predators and probably need both visual and chemical information to effectively avoid them. This is the first study looking at anti-predator behavior in poison frog tadpoles. We discuss how parental care might influence the expression of predator avoidance responses in tadpoles.

Nothing changes, nobody cares: understanding the experience of emergency nurses physically or verbally assaulted while providing care

INTRODUCTION

Workplace violence has been recognized as a violent crime that requires targeted responses from employers, law enforcement, and the community. According to data from the Bureau of Labor Statistics, the most common source of nonfatal injuries and illnesses requiring days away from work in the health care and social assistance industry was assault on the health care worker. What is not well understood are the precursors and sequelae of violence perpetrated against emergency nurses and other health care workers by patients and visitors. The purpose of this study was to better understand the experience of emergency nurses who have been physically or verbally assaulted while providing patient care in US emergency departments.

METHODS

The study was conducted using a qualitative descriptive exploratory design. The sample consisted of 46 written narratives submitted by e-mail by emergency nurses describing the experience of violence while providing care at work. Narrative analysis and constant comparison were used to identify emerging themes in the narratives.

RESULTS

"Environmental," "personal," and "cue recognition" were identified as the themes. Overall, nurses believed that violence was endemic to their workplace and that both limited recognition of cues indicating a high-risk person or environment and a culture of acceptance of violence were barriers to mitigation.

DISCUSSION

These findings are consistent with the extant literature but with an added contribution of clearly identifying an underlying cultural acceptance of violence in the emergency department, as well as a distinct lack of cue recognition, in this sample of emergency nurses.