Ontogenetic and short-term fluctuations in the residence depth of young pelagic stages of Munida gregaria in different zones of northern Patagonia

Separate Feeding Between the Pelagic Stage of the Squat Lobster Munida gregaria and the Larger Sized Zooplankton Crustacean Groups in the Beagle Channel as Revealed by Stable Isotopes

“…This also coincides with acoustic reports of juvenile M. gregaria in the BC where it reached maximum depths deeper than 80 m but that situated this species denser aggregations between 21 and 28 m depth (Diez et al, 2016(Diez et al, , 2018. In neither of these studies in the BC further north in the northern and central Chilean Patagonian zone (Castro et al, 2019;Meerhoff et al, 2019), diel vertical migrations were documented for the post-larval (juvenile or megalopa) stages.…”

“…Diel vertical migration has been reported for most of these groups in other locations, including the Patagonian region, but in other seasons (Castro et al, 1993;Hamame and Antezana, 2010;Valle-Levinson et al, 2014). In M. gregaria zoea diel changes in vertical distribution have been documented mainly for the earlier stages in northern Patagonia and, depending on the location, in synchrony with semidiurnal tides (Castro et al, 2011(Castro et al, , 2019. The vertical distribution of the pelagic M. gregaria in our study coincides with previous observations of post-larval stages in the Baker basin (47 • S) or the inner sea of Chiloé (42 • S), where their position has been associated with the halocline apparently to favor horizontal transport (Castro et al, 2019;Meerhoff et al, 2019).…”

“…In M. gregaria zoea diel changes in vertical distribution have been documented mainly for the earlier stages in northern Patagonia and, depending on the location, in synchrony with semidiurnal tides (Castro et al, 2011(Castro et al, , 2019. The vertical distribution of the pelagic M. gregaria in our study coincides with previous observations of post-larval stages in the Baker basin (47 • S) or the inner sea of Chiloé (42 • S), where their position has been associated with the halocline apparently to favor horizontal transport (Castro et al, 2019;Meerhoff et al, 2019). This also coincides with acoustic reports of juvenile M. gregaria in the BC where it reached maximum depths deeper than 80 m but that situated this species denser aggregations between 21 and 28 m depth (Diez et al, 2016(Diez et al, , 2018.…”

“…The species has two morphs, a benthic adult morph, originally named M. gregaria, and a post-larval-juvenile pelagic morph, originally named M. subrugosa, that can reach the size of adults while still in the water column (Pérez-Barros et al, 2008. While the depth distributions of both morphs have been reported, there are insufficient studies on shorter-term (diel, seasonal) variations in distributions of different sized pelagic stages in the water column (Meerhoff et al, 2013(Meerhoff et al, , 2014, with most reports on the zoea stages of development (Castro et al, 2011(Castro et al, , 2019. For these stages, ontogenetic migration from the inner channel zones of zoea release to offshore zones and back to inner areas as megalopa or juveniles, has been documented in northern Chilean Patagonian channels (León et al, 2008;Meerhoff et al, 2013Meerhoff et al, , 2014Mujica et al, 2013).…”

Predicting suitable coastal habitat for sei whales, southern right whales and dolphins around the Falkland Islands

“…Unfortunately, no studies have examined the spatio-temporal abundance of Munida or Themisto in the Falklands. Existing information on Munida from elsewhere on the Patagonian Shelf suggests that swarms remain in the same areas year-round but are larger and occur deeper in the water column during winter [ 44 ], and that diel vertical migration by various Munida life stages is less apparent than vertical movements related to the tidal cycle [ 47 ]. Although costly, the collection of targeted data on the abundance, distribution and behaviour of prey species, and particularly the collection of concurrent real-time data on prey biomass during whale surveys, may help to better explain sei whale occurrence in the Falklands.…”