National-scale marine bioregions for the Southwest Pacific

Existing marine bioregions covering the Pacific Ocean are conceptualised at spatial scales that are too broad for national marine spatial planning. Here, we developed the first combined oceanic and coastal marine bioregionalisation at national scales, delineating 262 deep-water and 103 reef-associated bioregions across the southwest Pacific. The deep-water bioregions were informed by thirty biophysical environmental variables. For reef-associated environments, records for 806 taxa at 7369 sites were used to predict the probability of observing taxa based on environmental variables. Both deep-water and reef-associated bioregions were defined with cluster analysis applied to the environmental variables and predicted species observation probabilities, respectively to classify areas with high taxonomic similarity. Local experts further refined the delineation of the bioregions at national scales for four countries. This work provides marine bioregions that enable the design of ecologically representative national systems of marine protected areas within offshore and inshore environments in the Pacific

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Not AvailableThe study presents the influence of 6-benzayladenine alone and in combination with gibberellic acid on growth and lateral branching of one-year-old ‘Oregon Spur’ apple nursery trees grafted on MM-106 rootstock. Different concentrations of BA and BA+GA3 (200, 300, 400, 500, 600 and 700 ppm) were applied three times at one week interval during second vegetative growth. Investigation reveal that Oregon Spur have strong apical dominance and plant applied with growth regulators resulted in a significant increase in number of feathers (0.58 to 6.18 per tree) compared to untreated control (0.18 per tree). However, BA alone has more significant effect on number of feathers (1.45 to 6.18 per tree) than BA+GA3 (0.58 to 4.35 per tree). Maximum number of feathers (6.18 per tree) has been obtained with 500 ppm BA treatment. This treatment also resulted in more uniform feather length (2.58 short and 2.55 medium length lateral branches per tree) and correct distribution of feathers along the trunk (20.63 cm branching zone) with appropriate average feathers crotch angle (54.74° from vertical). Furthermore, this treatment resulted in 100 per cent feathered trees compared to none in control and 2.88 trunk and mean feather diameter ratio compared to 1.54 in control. Some treatments with BA had a negative influence on the tree height. Whereas, most treatments increased trunk diameter and crotch angle compared to control.Not Availabl

Antipredator responses of koomal (Trichosurus vulpecula hypoleucus) against introduced and native predators

Antipredator behavior studies generally assess prey responses to single predator species although most real systems contain multiple species. In multi-predator environments prey ideally use antipredator responses that are effective against all predator species, although responses may only be effective against one predator and counterproductive for another. Multi-predator systems may also include introduced predators that the prey did not co-evolve with, so the prey may either fail to recognize their threat (level 1 naiveté), use ineffective responses (level 2 naiveté) or succumb to their superior hunting ability (level 3 naiveté). We analyzed microhabitat selection of an Australian marsupial (koomal, Trichosurus vulpecula hypoleucus) when faced with spatiotemporal differences in the activity/density levels of one native (chuditch, Dasyurus geoffroii) and two introduced predators (red fox, Vulpes vulpes; feral cat, Felis catus). From this, we inferred whether koomal recognized introduced predators as a threat, and whether they minimized predation risk by either staying close to trees and/or using open or dense microhabitats. Koomal remained close to escape trees regardless of the predator species present, or activity/density levels, suggesting koomal employ this behavior as a first line of defense. Koomal shifted to dense cover only under high risk scenarios (i.e., with multiple predator species present at high densities). When predation risk was low, koomal used open microhabitats, which likely provided benefits not associated with predator avoidance. Koomal did not exhibit level 1 naiveté, although further studies are required to determine if they exhibit higher levels of naiveté (2-3) against foxes and cats