Movement data provide a window - often our only window - into the cognitive, social and biological processes that underlie the behavioural ecology of animals in the wild. Robust methods for identifying and interpreting distinct modes of movement behaviour are of great importance, but complicated by the fact that movement data are complex, multivariate and dependent. Many different approaches to exploratory analysis of movement have been developed to answer similar questions, and practitioners are often at a loss for how to choose an appropriate tool for a specific question. We apply and compare four methodological approaches: first passage time (FPT), Bayesian partitioning of Markov models (BPMM), behavioural change point analysis (BCPA) and a fitted multistate random walk (MRW) to three simulated tracks and two animal trajectories - a sea lamprey (Petromyzon marinus) tracked for 12 h and a wolf (Canis lupus) tracked for 1 year. The simulations - in which, respectively, velocity, tortuosity and spatial bias change - highlight the sensitivity of all methods to model misspecification. Methods that do not account for autocorrelation in the movement variables lead to spurious change points, while methods that do not account for spatial bias completely miss changes in orientation. When applied to the animal data, the methods broadly agree on the structure of the movement behaviours. Important discrepancies, however, reflect differences in the assumptions and nature of the outputs. Important trade-offs are between the strength of the a priori assumptions (low in BCPA, high in MRW), complexity of output (high in the BCPA, low in the BPMM and MRW) and explanatory potential (highest in the MRW). The animal track analysis suggests some general principles for the exploratory analysis of movement data, including ways to exploit the strengths of the various methods. We argue for close and detailed exploratory analysis of movement before fitting complex movement models.

Here we confirm a long-standing anecdotal observation; the sea lamprey ( Petromyzon marinus ) actively avoids the odor emitted by decaying conspecifics. We extracted the semiochemical mixture produced by the putrefying carcasses of sea lampreys via Soxhlet extraction in ethanol and exposed groups of 10 migratory-phase lampreys to either the putrefaction extract (N = 8) or an ethanol control (N = 8) in a laboratory raceway. Sea lampreys rapidly avoided the putrefaction odor while exhibiting no response to the ethanol control. This response was elicited with a diluted mixture (1:373 000) and was maintained for 40 min (the duration of exposure), after which the lampreys quickly returned to their nominal distribution. The ease with which this odor is obtained, and the rapid and consistent behavioral response, suggests the substance will prove useful as a repellent in the sea lamprey control program carried out in the Laurentian Great Lakes.

14The sea lamprey Petromyzon marinus is an invasive pest in the Laurentian Great Lakes basin, 15 threatening the persistence of important commercial and recreational fisheries. There is 16 substantial interest in developing effective trapping practices via the application of behavior-17 modifying semiochemicals (odors). Here we report on the effectiveness of utilizing repellent and 18 attractant odors in a push-pull configuration, commonly employed to tackle invertebrate pests, to 19 improve trapping efficacy at permanent barriers to sea lamprey migration. When a half-stream 20 channel was activated by a naturally derived repellent odor (a putative alarm cue), we found that 21 sea lamprey located a trap entrance significantly faster than when no odor was present as a result 22 of their redistribution within the stream. The presence of a partial sex pheromone, acting as an 23 attractant within the trap, was not found to further decrease the time to when sea lamprey located 24 a trap entrance, relative to when the alarm cue alone was applied. Neither the application of 25 alarm cue singly, or alarm cue and partial sex pheromone in combination, was found to improve 26 the numbers of sea lamprey captured in the trap vs. when no odor was present -likely because 27 nominal capture rate during control trials was unusually high during the study period. 28Behavioural guidance using these odors has the potential to both improve control of invasive 29 non-native sea lamprey in the Great Lakes as well as improving the efficiency of fish passage 30 devices used in the restoration of threatened lamprey species elsewhere. 31

How sea lampreys (Petromyzon marinus) search for and select reproductive habitat is poorly understood. Manual tracking of acoustically tagged migrants confirms the hypothesis that sea lampreys transition from extensive search to intensive search upon encounter with river water and return to extensive search upon leaving the plume. In addition, we document a previously unknown search tactic used to localize river mouths termed coastal rebounding. Increased intensive search in the river plume and subsequent approach to the river mouth is hypothesized to occur as a consequence of detection of a pheromone released by river resident larvae that indicate the presence of high-quality reproductive habitat. Application of two synthesized pheromone components caused migrants to increase time spent searching a plume by 57%; applications did not increase the likelihood of river entry. These findings suggest that partial pheromones constitute information that facilitates the search for river entrances, but prove insufficient to affect the decision to select a habitat. Proposed management tactics that rely on luring migrants into rivers with larval odor may prove ineffective without a complete blend of pheromone components.