Spatial variation in reproduction in southern populations of the New Zealand bivalve <i>Paphies ventricosa</i> (Veneroida: Mesodesmatidae)

<div><p><i>Paphies ventricosa</i> is a large surf clam endemic to New Zealand, and whose populations have substantially declined during the past century owing to overfishing and habitat degradation. Poor recruitment is now evident, and therefore, understanding the reproductive patterns of <i>P. ventricosa</i> is a key to developing and implementing conservation strategies for the species. This study examines the reproductive cycle of <i>P. ventricosa</i> over one year in a population at Oreti Beach, Southland, the southernmost known extent of the species. At the same beach, we quantify spatial variation in reproduction among four sites using quarterly surveys. Reproductive status is quantified from body indices and histological examination of gonads. Based on changes in oocyte sizes, gametogenic stages and condition index, we observed a species with a primary spawning in spring and a second spawning event in autumn, with no resting phase but minimal reproductive activity over winter. Seasonal reproduction corresponded with warmer sea surface temperature and a peak in chlorophyll-a concentrations in the region. Small-scale (<15 km) variation in the timing of spawning was also evident along Oreti Beach, and these patterns maybe an important consideration when identifying areas that may be considered for conserving source populations.</p></div

Supplementary Table 1 from <i>In situ</i> developmental responses of tropical sea urchin embryos to ocean acidification conditions at naturally elevated <i>p</i>CO₂ vent sites

Carbonate chemistry, temperature and chlorophyll concentration at control and vent sites during Experiment 1 (Table 1A) and Experiment 2 (Table 1B) in Milne Bay, Papua New Guinea. Experiment 1 encompassed two independent trials, while Experiment 2 encompassed four independent trials. For each experiment and trial we report: (i) chemistry measurements based on TA/DIC measurements collected from water samples (N = 2 or 3) during daytime at two consecutive days during each experiments, and (ii) SeaFET mooring data on water temperature and pH are represented as average, minimum and maximum values measured during deployment

Supplementary Table 1. ;Supplementary Table 2. ;Supplementary Table 3. ;Supplementary Table 4 ;Supplementary Figure 1 from <i>In situ</i> developmental responses of tropical sea urchin embryos to ocean acidification conditions at naturally elevated <i>p</i>CO₂ vent sites

Carbonate chemistry, temperature and chlorophyll concentration at control and vent sites during Experiment 1 (Table 1A) and Experiment 2 (Table 1B) in Milne Bay, Papua New Guinea. Experiment 1 encompassed two independent trials, while Experiment 2 encompassed four independent trials. For each experiment and trial we report: (i) chemistry measurements based on TA/DIC measurements collected from water samples (N = 2 or 3) during daytime at two consecutive days during each experiments, and (ii) SeaFET mooring data on water temperature and pH are represented as average, minimum and maximum values measured during deployments.;Nested two-way ANOVA for total length (2A) and arm asymmetry (2B) for Echinometra spp. A larvae raised at Dobu control and vent sites at 24 and 48 hours exposure. The fixed factors (pH and time) are nested within the two consecutive experiments.;Nested two-way ANOVA for total length (3A) and arm asymmetry (3B) for 48-h old Echinometra spp. A larvae spawned from either Upa-Upasina vent or control adults and reciprocally transplanted to both Upa-Upasina control and vent sites. The fixed factors (pH and adult source) are nested within the two consecutive experiments.;Nested two-way ANOVA for total length (3A) and arm asymmetry (3B) for 48-h old Echinometra spp. A larvae spawned from either Upa-Upasina vent or control adults and reciprocally transplanted to both Upa-Upasina control and vent sites. The fixed factors (pH and adult source) are nested within the two consecutive experiments.;Seawater pH(T) measurements at control and vent sites for Dobu Island (A) and Upu-Upasina (B). Measurements are made using a seaFET pH/temperature logger that was moored at 2 - 3 m depth

Straight Line Foraging in Yellow-Eyed Penguins: New Insights into Cascading Fisheries Effects and Orientation Capabilities of Marine Predators

<div><p>Free-ranging marine predators rarely search for prey along straight lines because dynamic ocean processes usually require complex search strategies. If linear movement patterns occur they are usually associated with travelling events or migratory behaviour. However, recent fine scale tracking of flying seabirds has revealed straight-line movements while birds followed fishing vessels. Unlike flying seabirds, penguins are not known to target and follow fishing vessels. Yet yellow-eyed penguins from New Zealand often exhibit directed movement patterns while searching for prey at the seafloor, a behaviour that seems to contradict common movement ecology theories. While deploying GPS dive loggers on yellow-eyed penguins from the Otago Peninsula we found that the birds frequently followed straight lines for several kilometres with little horizontal deviation. In several cases individuals swam up and down the same line, while some of the lines were followed by more than one individual. Using a remote operated vehicle (ROV) we found a highly visible furrow on the seafloor most likely caused by an otter board of a demersal fish trawl, which ran in a straight line exactly matching the trajectory of a recent line identified from penguin tracks. We noted high abundances of benthic scavengers associated with fisheries-related bottom disturbance. While our data demonstrate the acute way-finding capabilities of benthic foraging yellow-eyed penguins, they also highlight how hidden cascading effects of coastal fisheries may alter behaviour and potentially even population dynamics of marine predators, an often overlooked fact in the examination of fisheries’ impacts. </p></div

Foraging patterns of Yellow-eyed penguins.

<p>Mid-shelf foraging tracks of yellow-eyed penguins recorded in 2004 (A), 2005 (B) and 2012 (C) that feature straight-line patterns. Foraging track segments in light grey represent outgoing and incoming stages of foraging trips; dark grey segments highlight the foraging stage. Dashed line segments indicate where linearity of the track is a result of interpolation. Track portions that met line criteria (see Methods) are highlighted in different colours; line identifiers shown in capital letters of the same colour. Small arrows in (D) indicate sites of ROV deployments in February 2013. Trips with lines from all three seasons are combined in (D).</p

Foraging parameters of yellow-eyed penguins fitted with GPS dive loggers.

<p>Foraging parameters of yellow-eyed penguins fitted with GPS dive loggers. </p

Screen capture of ROV footage recorded on line “C”.

<p>Main: Highly visible furrow running in a straight line along the seafloor at water depth of ca. 67 m. Note the echinoderms that have settled inside the furrow. Inset: Detail of blue cod in pursuit of ROV; scaling lasers represent 5 cm. See also (<a href="http://vimeo.com/64689982" target="_blank">http://vimeo.com/64689982</a>).</p

Comparison of basic foraging parameters in relation to breeding season and occurrence of linear patterns.

<p>Box-and-whiskers plots illustrate differences in foraging parameters between trips with and without linear patterns (A), and between the three breeding seasons (B & C). Bold horizontal lines indicate median and circles represent outliers. Note that graphs A and B are based on all recorded foraging trips, while for C only trips that met straight line criteria were used. Sample sizes are provided below x-axis labels.</p

Fertilisation success of <i>A. planci</i> oocytes across a range of sperm concentrations (10²–10⁸ sperm ml⁻¹) under three pH/<i>p</i>CO₂ conditions.

<p>Solid lines represent best-fit curves under three different pH/<i>p</i>CO₂ scenarios, and corresponding dashed lines are 95% confidence intervals.</p

A) Sperm velocity and percentage of motile sperm (% motility) for the three different treatments (Factor Treatment, see ANOVA in Table 3). B) Differences in sperm velocity and percentage of motile sperm between individual males (Factor Male, see ANOVA in Table 3. Error bars represent 1 standard error. Averages with different letters are significantly different (p<0.05, Tukey-Kramer posthoc tests).

<p>A) Sperm velocity and percentage of motile sperm (% motility) for the three different treatments (Factor Treatment, see ANOVA in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082938#pone-0082938-t003" target="_blank">Table 3</a>). B) Differences in sperm velocity and percentage of motile sperm between individual males (Factor Male, see ANOVA in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082938#pone-0082938-t003" target="_blank">Table 3</a>. Error bars represent 1 standard error. Averages with different letters are significantly different (p<0.05, Tukey-Kramer posthoc tests).</p