Temperature and embryonic development in relation to spawning and field occurrence of larvae of three Antarctic echinoderms

first_imgThe effects of temperature on development and viability were measured at 14 levels between -2{deg}C and +3{deg}C on embryos of two asteroids (Odontaster validus and Odontaster meridionalis) and an echinoid (Sterechinus neumayeri) from Signy Island, Antarctica. Development rates were 2 to 10 times slower than those for temperate or tropical echinoderms, with times to hatching up to 240 h. Development rates for the two asteroids differed by 1.15 x, and rates for both species approximately doubled over the experimental temperature range. In O. validus, embryo viability was independent of temperature, but in O. meridionalis viability declined with increasing temperature. Development rates for S. neumayeri were little affected by temperature above +0.2{deg}C, but declined rapidly at lower temperatures. Conversely, the number of nonviable eggs was low and constant below +1.7{deg}C, but rose rapidly at higher temperatures. A window of optimal temperature, between +0.2{deg}C and +1.7{deg}C, has therefore been proposed for development time and embryo viability in this population of S. neumayeri. Spawning trials and field observations of larvae indicated that the time of gamete release and periods of larval development in S. neumayeri coincided with austral summer sea temperatures in the same window. Embryos of O. meridionalis and O. validus are released in winter, when temperatures are constantly below -1.6{deg}C. Comparison of the different strategies suggests that larval food supply and predation during planktonic phases are not the dominant ecological factors for these specieslast_img read more

Penguin-mounted cameras glimpse underwater group behaviour

first_imgMarine birds and mammals spend most of their lives in the open ocean far from human observation, which makes obtaining information about their foraging behaviour difficult. Here, we show, by use of a miniaturized digital camera system, the first direct evidence (to our knowledge) of underwater group behaviour in free-ranging penguins. Penguins swim closely accompanied by other bird(s) during 24% of their possible foraging dives. This finding confirms that such miniaturized camera technology has broad applicability for advancing our knowledge about the previously unknown social interactions of marine animals at depth.last_img read more

Environmental forcing and Southern Ocean marine predator populations: effects of climate change and variability

first_imgThe Southern Ocean is a major component within the global ocean and climate system and potentially the location where the most rapid climate change is most likely to happen, particularly in the high-latitude polar regions. In these regions, even small temperature changes can potentially lead to major environmental perturbations. Climate change is likely to be regional and may be expressed in various ways, including alterations to climate and weather patterns across a variety of time-scales that include changes to the long interdecadal background signals such as the development of the El Nino-Southern Oscillation (ENSO). Oscillating climate signals such as ENSO potentially provide a unique opportunity to explore how biological communities respond to change. This approach is based on the premise that biological responses to shorter-term sub-decadal climate variability signals are potentially the best predictor of biological responses over longer time-scales. Around the Southern Ocean, marine predator populations show periodicity in breeding performance and productivity, with relationships with the environment driven by physical forcing from the ENSO region in the Pacific. Wherever examined, these relationships are congruent with mid-trophic-level processes that are also correlated with environmental variability. The short-term changes to ecosystem structure and function observed during ENSO events herald potential long-term changes that may ensue following regional climate change. For example, in the South Atlantic, failure of Antarctic krill recruitment will inevitably foreshadow recruitment failures in a range of higher trophic-level marine predators. Where predator species are not able to accommodate by switching to other prey species, population-level changes will follow. The Southern Ocean, though oceano-graphically interconnected, is not a single ecosystem and different areas are dominated by different food webs. Where species occupy different positions in different regional food webs, there is the potential to make predictions about future change scenarios.last_img read more

Oceanographic processes near the Filchner Sill – plans for fieldwork in 2007

first_imgIntroductionOver the Antarctic continental shelves, the focus of attention has been on the export of cold denseshelf waters to the world’s deep ocean and their contribution to Antarctic Bottom Water (AABW)production. Far less attention has been given to the import, onto the continental shelves, of surface and warm deep waters, which are key components of the heat, salt and mass budgets for the shelf seas. In order to quantify these budgets, mechanisms that control the rate of cross-shelfexchange need to be identified if we are to better understand the interactions between the Antarctic shelf seas and adjacent oceans. In the southeastern Weddell Sea, east of 26°W, the water masses over the narrow continentalshelf are separated from the deep ocean by a series of fronts and associated currents. During winter, cooling leads to the formation of Winter Water (WW), while over the continental shelf water masses are freshened by glacial melt from the ice shelves that fringe the region [Fahrbachet al., 1994]. This cross-shelf density gradient supports a westward slope front current. In addition, the prevailing easterly winds produce a surface Ekman transport, leading to an increase in sea surface elevation toward the coast and a downwelling of the isopycnals that both deepensthe interface between the WW and the underlying Weddell Deep Water (WDW) and supports a westward coastal current. In the southeastern Weddell Sea where the open shelf is very narrow, these currents effectively merge and are referred to as the Antarctic Coastal Current [Fahrbach etal., 1992]. Once the coastal current passes the Stancomb-Wills Ice Stream, which overhangs the shelf break,the continental shelf broadens and the current separates into coastal and slope components [Foster and Carmack, 1976]. The coastal component heads south towards Brunt Ice Shelf while the slope component flows west towards the Filchner Sill. North of Helmert Bank, WDW is found below the depth of both the shelf break and the troughs that cut some 200 m deeper into the surrounding shelf. Nevertheless, despite the physical and dynamic barriers associated with the shelf break, WDW is able to upwell and access the continental shelf in a modified form. These intrusions of Modified Weddell Deep Water (MWDW) occur at various locations along the shelf break, although only two persist beyond the shelf break region and extend southwards towardFilchner Ronne Ice Front. The aim of the forthcoming cruise in early 2007 is to identify the shelf break processes that control the upwelling of MWDW onto the shelf, and determine the flux of heat, salt and mass across the continental shelf break around the Filchner Sill region and alongthe Luitpold Coast (Figure 1).last_img read more

Emperor penguins breeding on iceshelves

first_imgWe describe a new breeding behaviour discovered in emperor penguins; utilizing satellite and aerial-survey observations four emperor penguin breeding colonies have been recorded as existing on ice-shelves. Emperors have previously been considered as a sea-ice obligate species, with 44 of the 46 colonies located on sea-ice (the other two small colonies are on land). Of the colonies found on ice-shelves, two are newly discovered, and these have been recorded on shelves every season that they have been observed, the other two have been recorded both on ice-shelves and sea-ice in different breeding seasons. We conduct two analyses; the first using synthetic aperture radar data to assess why the largest of the four colonies, for which we have most data, locates sometimes on the shelf and sometimes on the sea-ice, and find that in years where the sea-ice forms late, the colony relocates onto the ice-shelf. The second analysis uses a number of environmental variables to test the habitat marginality of all emperor penguin breeding sites. We find that three of the four colonies reported in this study are in the most northerly, warmest conditions where sea-ice is often sub-optimal. The emperor penguin’s reliance on sea-ice as a breeding platform coupled with recent concerns over changed sea-ice patterns consequent on regional warming, has led to their designation as “near threatened” in the IUCN red list. Current climate models predict that future loss of sea-ice around the Antarctic coastline will negatively impact emperor numbers; recent estimates suggest a halving of the population by 2052. The discovery of this new breeding behaviour at marginal sites could mitigate some of the consequences of sea-ice loss; potential benefits and whether these are permanent or temporary need to be considered and understood before further attempts are made to predict the population trajectory of this iconic species.last_img read more

Open access data in polar and cryospheric remote sensing

first_imgThis paper aims to introduce the main types and sources of remotely sensed data that are freely available and have cryospheric applications. We describe aerial and satellite photography, satellite-borne visible, near-infrared and thermal infrared sensors, synthetic aperture radar, passive microwave imagers and active microwave scatterometers. We consider the availability and practical utility of archival data, dating back in some cases to the 1920s for aerial photography and the 1960s for satellite imagery, the data that are being collected today and the prospects for future data collection; in all cases, with a focus on data that are openly accessible. Derived data products are increasingly available, and we give examples of such products of particular value in polar and cryospheric research. We also discuss the availability and applicability of free and, where possible, open-source software tools for reading and processing remotely sensed data. The paper concludes with a discussion of open data access within polar and cryospheric sciences, considering trends in data discoverability, access, sharing and use.last_img read more

Predicting climate change impacts on maritime Antarctic soils: A space-for-time substitution study

first_imgWe report a space-for-time substitution study predicting the impacts of climate change on vegetated maritime Antarctic soils. Analyses of soils from under Deschampsia antarctica sampled from three islands along a 2,200 km climatic gradient indicated that those from sub-Antarctica had higher moisture, organic matter and carbon (C) concentrations, more depleted δ13C values, lower concentrations of the fungal biomarker ergosterol and higher concentrations of bacterial PLFA biomarkers and plant wax n-alkane biomarkers than those from maritime Antarctica. Shallow soils (2 cm depth) were wetter, and had higher concentrations of organic matter, ergosterol and bacterial PLFAs, than deeper soils (4 cm and 8 cm depths). Correlative analyses indicated that factors associated with climate change (increased soil moisture, C and organic matter concentrations, and depleted δ13C contents) are likely to give rise to increases in Gram negative bacteria, and decreases in Gram positive bacteria and fungi, in maritime Antarctic soils. Bomb-14C analyses indicated that sub-Antarctic soils at all depths contained significant amounts of modern 14C (C fixed from the atmosphere post c. 1955), whereas modern 14C was restricted to depths of 2 cm and 4 cm in maritime Antarctica. The oldest C (c. 1,745 years BP) was present in the southernmost soil. The higher nitrogen (N) concentrations and δ15N values recorded in the southernmost soil were attributed to N inputs from bird guano. Based on these analyses, we conclude that 5–8 °C rises in air temperature, together with associated increases in precipitation, are likely to have substantial impacts on maritime Antarctic soils, but that, at the rates of climate warming predicted under moderate greenhouse gas emission scenarios, these impacts are likely to take at least a century to manifest themselves.last_img read more

Oil bioremediation in the marine environment of Antarctica: A review and bibliometric keyword cluster analysis

first_imgBioremediation of hydrocarbons has received much attention in recent decades, particularly relating to fuel and other oils. While of great relevance globally, there has recently been increasing interest in hydrocarbon bioremediation in the marine environments of Antarctica. To provide an objective assessment of the research interest in this field we used VOSviewer software to analyze publication data obtained from the ScienceDirect database covering the period 1970 to the present, but with a primary focus on the years 2000–2020. A bibliometric analysis of the database allowed identification of the co-occurrence of keywords. There was an increasing trend over time for publications relating to oil bioremediation in maritime Antarctica, including both studies on marine bioremediation and of the metabolic pathways of hydrocarbon degradation. Studies of marine anaerobic degradation remain under-represented compared to those of aerobic degradation. Emerging keywords in recent years included bioprospecting, metagenomic, bioindicator, and giving insight into changing research foci, such as increasing attention to microbial diversity. The study of microbial genomes using metagenomic approaches or whole genome studies is increasing rapidly and is likely to drive emerging fields in future, including rapid expansion of bioprospecting in diverse fields of biotechnology.last_img read more

Prep Sports Roundup: 3/24

first_img Tags: ALA/Baseball/Boys Soccer/Delta/Enterprise/Juab/Manti/Payson/South Sevier FacebookTwitterLinkedInEmailBoys SoccerNon-RegionPAYSON, Utah-Brayden Gonder, Jager Springer and Trevor Burton each scored as the Delta Rabbits outlasted Payson 3-2 Saturday in non-region boys soccer action.BaseballRegion 14SPANISH FORK, Utah-Tucker Memmott tripled and Joey Aagard doubled as the Juab Wasps downed ALA 8-6 Saturday in Region 14 baseball action.Non-RegionENTERPRISE, Utah-Spencer Laub doubled while Levi Randall earned the win on the mound as the Enterprise Wolves downed Manti 6-2 in non-region baseball action Saturday.ENTERPRISE, Utah-Levi Randall doubled and Spencer Laub took the win on the mound, helping the Enterprise Wolves blank South Sevier 2-0 Saturday in non-region baseball action.ENTERPRISE, Utah-Peydon Wood had two hits and earned the win on the mound as the South Sevier Rams beat the Manti Templars 3-0 in non-region baseball action Saturday. Brennen Hunt added a double in the win for the Rams. Brad James March 24, 2018 /Sports News – Local Prep Sports Roundup: 3/24 Written bylast_img read more

Union rout Real Salt Lake 4-1

first_img FacebookTwitterLinkedInEmailCHESTER, Pa. (AP) — Marcus Epps and Borek Dockal scored in the first half and the Philadelphia Union added two more in the second to beat Real Salt Lake 4-1 on Saturday night.Fabrice-Jean Picault had a 40-yard run up the left channel to set up the opening goal in the 21st minute, rounding his defender and slotting a cross through several defenders to find Epps for the finish.Dockal chipped home Alejandro Bedoya’s through ball to make it 2-0 for the Union (4-5-2) in the 34th minute.Damir Kreilach pulled Real Salt Lake (4-6-1) to 2-1 in the 65th minute. Sebastian Saucedo made a run at the end line and cut the pass back to Kreilach.Ilsinho capped a fast break to make it 3-1 in the 74th minute, and Keegan Rosenberry drove one home from 25 yards to cap the scoring in the 81st. Written by Robert Lovell Tags: MLS/Real Salt Lake/Soccer May 19, 2018 /Sports News – Local Union rout Real Salt Lake 4-1last_img read more

Bees Outlast Rainiers

first_imgAugust 10, 2018 /Sports News – Local Bees Outlast Rainiers FacebookTwitterLinkedInEmail(Salt Lake City, UT)  —  The Bees gave up three runs in the ninth inning but held on to outlast the Rainiers 8-7 at Smith’s Ballpark.Jared Walsh and Jabari Blash each homered for Salt Lake in the win.The series continues tonight. Tags: Baseball/PCL/Salt Lake Bees Written by Robert Lovelllast_img

Tate throws for 349 yards, 5 TDs as Arizona routs S. Utah

first_img FacebookTwitterLinkedInEmailTUSCON, Ariz. (AP) — Khalil Tate passed for a career-best 349 yards and five touchdowns, then sat out most of the fourth quarter and Arizona gave Kevin Sumlin his first victory as Wildcats coach with a 62-31 rout of Southern Utah on Saturday night.Tate needed just 13 completions, in 20 attempts, to amass his big numbers. His five touchdowns, which matched a career best, covered 17, 11, 2, 65 and 75 yards.Arizona (1-2) scored 31 consecutive points after Southern Utah (0-3), an FCS school coming off a 45-28 loss at Oregon State, tied it at 17-17 late in the second quarter.J.J. Taylor returned a kickoff 84 yards for a touchdown for the Wildcats, his first kickoff return for a score in his college career.Arizona, coming off a home loss to BYU and a dispiriting 45-18 rout at Houston, had 626 total yards to Southern Utah’s 463 despite running 60 plays to the Thunderbirds’ 98.Tate tweaked an ankle early in the Houston game and hasn’t shown his dynamic running ability since. He didn’t need to against Southern Utah. His passing was plenty.In the third quarter alone, Tate was 6-of-8 for 215 yards and three touchdowns. That included a 65-yard TD pass to Shun Brown and a pretty over-the-shoulder pass to Shawn Poindexter for a 75-yard score.After Southern Utah rallied to tie it at 17-17 with 2:39 left in the first half, Tate quickly got the Wildcats back in the lead for good.His 30-yard pass to Tony Ellison was the highlight of the eight-play, 67-yard drive. From the Thunderbirds’ 11, Tate bought time running to his right and threw in the end zone to Brown for the TD.The Wildcats took the second-half kickoff and put together another quick scoring drive. With the help of an unsportsmanlike conduct penalty, Arizona went 67 yards in five plays in just 1:55. Tate threw two yards to Cedric Peterson for the score and it was 31-17.Arizona scored the first time it had the ball, Tate throwing 17 yards to Ellison for the score.Manny Berz kicked a 32-yard field goal on the first play of the second quarter to cut Arizona’s lead to 7-3 but Taylor took the subsequent kickoff, dashed to an opening on his left and raced down the sideline 84 yards for the TD and it was 14-3.Southern Utah went 75 yards in 13 plays, Chris Helbig keeping on a two-yard scoring run to tie it at 17-17 with 2:39 left in the half.In the first half, the Thunderbirds ran 51 plays to Arizona’s 25 but trailed by seven.THE TAKEAWAYSouthern Utah: After an 0-3 start, the Thunderbirds will be glad to be back in Big Sky Conference play, where their offense should be entertaining and keep them in games as they defend their Big Sky title.Arizona: Even though the opponent was from the FCS ranks, Arizona at least got a first win for coach Kevin Sumlin. Tate showed off his passing talent but didn’t run much at all. It wasn’t needed in this one but it will be in Pac-12 play down the line.UP NEXTSouthern Utah begins Big Sky Conference play at Northern Arizona next Saturday night.Arizona opens Pac-12 play at Oregon State. Written by Tags: Football/SUU Thunderbirds September 16, 2018 /Sports News – Local Tate throws for 349 yards, 5 TDs as Arizona routs S. Utah Associated Presslast_img read more

Former NFL player Jeff Rohrer on coming out and same-sex marriage: ‘I followed my heart’

first_img“I feared the worst with my kids, I feared the worst with my family, I feared the worst with my friends, I feared the worst with my teammates,” he said. “I feared the worst with past teammates and I would say 99.4 percent I was wrong.”Ross and Rohrer said they’ve heard from other athletes grappling with the same issues.“There was a young kid playing, I don’t think it was professional baseball I think it was college baseball, and he basically sent along a message saying thank you so much and I need advice,” Ross said.Copyright © 2018, ABC Radio. All rights reserved. Written by November 21, 2018 /Sports News – National Former NFL player Jeff Rohrer on coming out and same-sex marriage: ‘I followed my heart’ FacebookTwitterLinkedInEmailjoshuaandjeffrey/Instagram(NEW  YORK) — When retired NFL player Jeff Rohrer tied the knot with Joshua Ross over the weekend, becoming the first ex-NFL player to be in a same-sex marriage, he said the decision was a relief after living in the closet for most of his life.“I followed my heart,” the 59-year-old told ABC News.It wasn’t until he divorced his wife a decade ago that he was able to truly tap into his feelings.“I was living the life of a straight man for most of my life,” he said. “My generation, it just was never part of the narrative.”Rohrer, an ex-Cowboys player, married 36-year-old Ross, the “Real Housewives of Beverly Hills” aesthetician, over the weekend in front of more than 100 family and friends.Rohrer came out to the world last week. View this post on Instagram “To be fully seen by somebody, then, and be loved anyhow–this is a human offering that can border on miraculous.” – Elizabeth GilbertA post shared by Josh & Jeff Rohrer (@joshuaandjeffrey) on Nov 14, 2018 at 8:23am PST Beau Lundlast_img read more

Chicago Bulls waive Carmelo Anthony

first_img Written by February 1, 2019 /Sports News – National Chicago Bulls waive Carmelo Anthony FacebookTwitterLinkedInEmailPhil Ellsworth/ESPN Images(NEW YORK) — The Chicago Bulls have waived forward Carmelo Anthony, allowing him to enter free agency, according to ESPN’s Adrian Wojnarowski.The Bulls originally acquired Anthony, along with cash considerations, in a trade with the Houston Rockets. Anthony never played a game in a Bulls uniform as the team planned to waive him barring any trade offers.It’s the fourth team Anthony has landed on in two seasons. After an unsuccessful stint with the Oklahoma City Thunder, he was traded to the Hawks in exchange for point guard Dennis Schroeder. The Hawks then waived the 10-time All Star, allowing him to sign with the Rockets.Anthony only played in ten games for the Rockets before head coach Mike D’Antoni decided he did not fit with the roster.“It wasn’t fair for him as a Hall of Fame player to play in a role that wasn’t good for him,” D’Antoni told reporters at the time. “It wasn’t a fit.”Anthony is now free to sign with any team of his choosing, with the Lakers considered the frontrunner as he is good friends with current Laker LeBron James. The Lakers would need to open up a roster spot to sign Anthony, something that could happen if the team manages to pull off a trade for New Orleans Pelicans star Anthony Davis.Copyright © 2019, ABC Radio. All rights reserved.center_img Beau Lundlast_img read more

Mitchell, Crowder help Jazz crush tired Timberwolves 120-100

first_imgShe implored fans to enjoy the competition and cheer the Jazz as loudly as ever but cautioned, “No one wins when respect goes away.” JAZZ OWNER SETS TONE The Timberwolves didn’t arrive in Salt Lake City until Thursday morning due to a severe snowstorm in Denver that prevented the team from flying. The team showed up for its charter flight a little after 10 a.m. on Wednesday but was stranded at the airport for nearly 10 hours because of high winds before returning to the hotel. Associated Press Mitchell converted a scintillating drive and dunk on the baseline and then a tough lay-in from the right angle. The game was within single digits most of the way, but the Jazz led by 24 in the closing minutes as the Timberwolves ran out of steam. Andrew Wiggins scored 14 points but shot 6 of 17. Tyus Jones had 12 points and nine assists for the Wolves. Karl-Anthony Towns had 26 points, including 14 in the third quarter as the Timberwolves drew within 71-70. Utah finished the period on a scoring burst and led 91-81 entering the fourth on a rare dunk by Joe Ingles. In his nine games since the All-Star break, Towns has averaged 34 points and 13.4 rebounds but looked frustrated at times against the length of Gobert and fouled out as he tried to bull through the Jazz center on a baseline drive with 4:13 remaining. Players from both teams listened intently and applauded the speech. Jazz owner Gail Miller released a statement and spoke to the crowd prior to the game to address an encounter between Oklahoma City star Russell Westbrook and a fan Tuesday. Utah permanently banned the fan from all arena events, and Westbrook was fined $25,000 by the league. FacebookTwitterLinkedInEmailSALT LAKE CITY (AP) — Donovan Mitchell scored 24 points, Jae Crowder had 18 and the Utah Jazz beat the travel-weary Minnesota Timberwolves 120-100 on Thursday night. Miller, who has owned the team for 34 years with her late husband Larry, implored the crowd to do better and said, “We are not a racist community.” Jazz: Host Brooklyn on Saturday. Timberwolves: Derrick Rose (elbow), Jeff Teague (foot), Luol Deng (Achilles) and Robert Covington (knee) all missed the game for Minnesota. … Towns caught Mitchell in the back of the head during a scramble for a rebound and received a Flagrant 1 foul. … The Timberwolves went 5 for 24 on 3-point attempts. TIP-INS Derrick Favors had 17 points and 11 rebounds and Ruby Gobert contributed 10 points and 13 boards for the Jazz, who played Wednesday night but didn’t have nearly the travel adventures that beset Minnesota. Tags: Donovan Mitchell/Jae Crowder/NBA/Utah Jazz March 14, 2019 /Sports News – Local Mitchell, Crowder help Jazz crush tired Timberwolves 120-100 Utah claimed the season series 3-1 and moved into a tie for sixth in the tight Western Conference. Jazz: Dante Exum, who missed 25 games with an ankle issue and only returned Monday, left the game after three minutes with knee soreness. … Utah outrebounded Minnesota 49-38. … The Jazz had 30 assists on their 44 field goals. “We moved the ball, that’s what it was,” Crowder said. UP NEXT Written by Timberwolves: Visit Houston on Sunday.last_img read more

Utah Baseball Falls at Utah Valley, 6-3

first_img FacebookTwitterLinkedInEmailOREM, Utah – Utah dropped its midweek game to Utah Valley in Orem, Utah 6-3 on Tuesday night.Jayden Kiernan got the start at catcher and came up big at the plate going 2-3 with all three of the team’s RBI.After UVU plated the first run of the game, Utah came right back in the second inning scoring two runs on two hits all with two outs in the inning. After a Chase Fernlund single and a Briley Knight walk, Kiernan came through with a double to put Utah on top, 2-1.The Wolverines hit a two-run homer to go back in front in the sixth, but it didn’t last long as Kiernan struck again with a single down the right field line to score Moeller to tie things back up.In front of their home crowd, Utah Valley took the lead once again scoring three runs on four hits in the eighth. The Utes brought the tying run to the plate in the ninth inning, but couldn’t come back a third time.Utah’s starter Dustin Schramm pitched 3.0 innings and only gave up the one run that was unearned.In all, four pitchers threw for Utah and Nick Caviglia took the loss on the night.The Utes had nine hits on the night. Chandler Anderson went 2-4 at the plate joining Kiernan with two hits. Written by Tags: Utah Utes Baseball/UVU Wolverines Baseball April 23, 2019 /Sports News – Local Utah Baseball Falls at Utah Valley, 6-3center_img Robert Lovell Utah and Utah Valley split the series this season as each team won on their home field.Utah will stay on the road as they travel to Los Angeles, California this weekend to take on No. 1 UCLA starting Friday, April 26 at 7 p.m. MT.last_img read more