Introduction

“It is a somewhat remarkable fact that not withstanding the extreme popularity of the subject of Birds’ Nests, no book has yet been published entirely devoted to these beautiful and curious objects. And yet their study — the science of Caliology — is one of the most fascinating branches of Ornithology, perhaps more intimately connected with those difficult problems and questions relating to the mental attributes of what man in his ignorance is pleased to consider the ” lower animals,” than any other. Indeed, there are many of us who would fain deny the existence of any reasoning faculties whatever in birds, classing their expression in a thousand different ways, all under the vague, meaningless and ridiculous term “Instinct.”

A bird’s nest is the most graphic mirror of a bird’s mind. It is the most palpable example of those reasoning, thinking qualities with which these creatures are unquestionably very highly endowed.

Evidence of this reasoning power confronts the student of Birds’ Nests as he gazes upon each procreant cradle, no matter how crude on the one hand, or how elaborate on the other…”

The role of cognition 

Building a nest to hatch its eggs and raise its young in is probably one of the most important things  a bird will do in its life time. The choices it makes about what sort of nest to build and what material to build it with will have a significant impact on the success of a nesting attempt. Despite some evidence that some learning is involved in such choices, nest building has historically been assumed to be largely genetically predetermined and inflexible.  However, we believe that the ability to learn about which materials work best and refine building techniques would be so advantageous for improving the nest structure and therefore reproductive success, that learning and memory are probably more important to this process than has previously been considered. We are currently investigating the role of learning and memory in material choice and nest construction behaviour in both Weaverbirds and Zebra Finches.

Efficient exploitation of food resources is vital to animals survival and involves a number of different challenges including: finding food, remembering which resources provide the best quality food (e.g. flowers of a certain colour, in a certain place or at a certain time of day), remembering when food is available, assessing the quality of food (e.g. by taste or post ingestive feedback), choosing between resources of similar quality that differ in how variable they are, and choosing a optimal routes between different locations (e.g. traplining). We are interested in what aspect of resources animals pay attention to, how they assess them and how good they are at learning about and remembering them.

Most of our work is conducted in the Alberta, Canada with wild rufus hummingbirds (Selasphorus rufus). These nectar feeding birds are very bold so we can get close to them and are territorial so we can work with one individual at a time. Their simple sugar diet makes it easy for us to calculate how much energy they are obtaining from their meals and as they feed every ten minutes or so we can quickly gather enough data to answer our questions.

Vocalisations are important cues or signals that allow animals to communicate with one another. We are interested in what information vocalisations contain and how they are learnt.