Linear tracks and restricted temperature ranges characterise penguin foraging pathways

first_imgMarine predators are thought to follow sophisticated scale-dependent search strategies when seeking patchy and unpredictable prey. However, fine-scale information about these strategies has hitherto been difficult to obtain for diving predators that often remain at the sea surface for only limited periods of time. Using ARGOS telemetry and novel, low-powered, archival GPS, we followed the fine-scale at-sea behaviour of king penguins breeding on South Georgia. Results revealed that foraging pathways were generally linear, except at the finest scale, where movements probably reflected either fine-scale searching behaviour, or fine-scale random movements associated with having found prey. King penguins focused 45% of their foraging effort in waters with a specific surface temperature (5.0 to 5.5 degrees C) – an environmental cue potentially important in helping them locate prey, thereby reducing their need to expend energy in area-restricted search patterns. Within these waters, penguins slowed down and increased their dive effort and degree of meandering. First Passage Time analysis revealed that penguins focused much of their effort at local scales, generally in areas with a radius of 2 km. In these areas, penguins dived marginally deeper and targeted waters that, were significantly warmer at the bottom of their dives. Such information about fine-scale foraging behaviour will help increase our understanding of the environmental correlates that characterise areas where marine predators exploit their prey. The scale of these behavioural processes is better resolved using the fine-scale temporal and spatial resolution of GPS tracking data.last_img read more

Divergent transcriptomic responses to repeated and single cold exposures in Drosophila melanogaster

first_imgInsects in the field are exposed to multiple bouts of cold, and there is increasing evidence that the fitness consequences of repeated cold exposure differ from the impacts of a single cold exposure. We tested the hypothesis that different kinds of cold exposure (in this case, single short, prolonged and repeated cold exposure) would result in differential gene expression. We exposed 3 day old adult female wild-type Drosophila melanogaster (Diptera: Drosophilidae) to –0.5°C for a single 2 h exposure, a single 10 h exposure, or five 2 h exposures on consecutive days, and extracted RNA after 6 h of recovery. Global gene expression was quantified using an oligonucleotide microarray and validated with real-time PCR using different biological replicates. We identified 76 genes upregulated in response to multiple cold exposure, 69 in response to prolonged cold exposure and 20 genes upregulated in response to a single short cold exposure, with a small amount of overlap between treatments. Three genes – Turandot A, Hephaestus and CG11374 – were upregulated in response to all three cold exposure treatments. Key functional groups upregulated include genes associated with muscle structure and function, the immune response, stress response, carbohydrate metabolism and egg production. We conclude that cold exposure has wide-ranging effects on gene expression in D. melanogaster and that increased duration or frequency of cold exposure has impacts different to those of a single short cold exposure. This has important implications for extrapolating laboratory studies of insect overwintering that are based on only a single cold exposure.last_img read more

Seabird colony effects on soil properties and vegetation zonation patterns on King George Island, Maritime Antarctic

first_imgSeabirds are among the most important vectors transferring biogenic compounds from the sea onto land in the polar regions and, consequently, influencing the properties of soil and vegetation. We studied the influence of bird colonies (Adélie penguin Pygoscelis adeliae, gentoo penguin P. papua and giant petrels Macronectes giganteus) on soil properties and plant communities on King George Island, Maritime Antarctic. We designated seven transects, each starting from the colony edge and running to a natural boundary feature, which were divided into contiguous sample plots where we identified specific plant taxa (Prasiola crispa, Deschampsia antarctica, Colobanthus quitensis, Usnea sp.), as well as hydrophilous and xerophilous ecological groups of mosses. Based on percentage contributions of each of these taxa, we distinguished six distinct vegetation zones along the transects, in which we measured physical (moisture, conductivity and pH) and chemical (NO3 −, NO2 −, NH4 +, K+ and PO4 3− content) soil parameters. Our study confirmed that, with increasing distance from bird colonies, the concentration of nutrients and soil conductivity decreased, while pH increased. The vegetation zones were clearly related to this gradient of seabird colony influence and occurred in the same sequence for all three bird species examined, although the largest colony of Adélie penguins had the strongest effect on vegetation. Similarly, the physical and chemical soil properties did not differ significantly between the colonieslast_img read more

Implementation of a geometrically informed and energetically constrained mesoscale eddy parameterization in an ocean circulation model

first_imgThe global stratification and circulation, and their sensitivities to changes in forcing, depend crucially on the representation of the mesoscale eddy field in a numerical ocean circulation model. Here, a geometrically informed and energetically constrained parameterization framework for mesoscale eddies — termed GEOMETRIC — is proposed and implemented in three-dimensional channel and sector models. The GEOMETRIC framework closes eddy buoyancy fluxes according to the standard Gent–McWilliams scheme, but with the eddy transfer coefficient constrained by the depth-integrated eddy energy field, provided through a prognostic eddy energy budget evolving with the mean state. It is found that coarse resolution models employing GEOMETRIC display broad agreement in the sensitivity of the circumpolar transport, meridional overturning circulation and depth-integrated eddy energy pattern to surface wind stress as compared with analogous reference calculations at eddy permitting resolutions. Notably, eddy saturation — the insensitivity of the time-mean circumpolar transport to changes in wind forcing — is found in the coarse resolution sector model. In contrast, differences in the sensitivity of the depth-integrated eddy energy are found in model calculations in the channel experiments that vary the eddy energy dissipation, attributed to the simple prognostic eddy energy equation employed. Further improvements to the GEOMETRIC framework require a shift in focus from how to close for eddy buoyancy fluxes to the representation of eddy energetics.last_img read more

A Horizon Scan of Emerging Global Biological Conservation Issues for 2020.

first_imgIn this horizon scan, we highlight 15 emerging issues of potential relevance to global conservation in 2020. Seven relate to potentially extensive changes in vegetation or ecological systems. These changes are either relatively new, for example, conversion of kelp forests to simpler macroalgal systems, or may occur in the future, for example, as a result of the derivation of nanocelluose from wood or the rapid expansion of small hydropower schemes. Other topics highlight potential changes in national legislation that may have global effect on international agreements. Our panel of 23 scientists and practitioners selected these issues using a modified version of the Delphi technique from a long-list of 89 potential topics.last_img

Routine metabolism of Antarctic krill (Euphausia superba) in South Georgia waters: Absence of metabolic compensation at its range edge

first_imgRoutine respiration rates in the South Georgia stock of Antarctic krill (Euphausia superba) were measured to compare with previously published measurements on stocks from colder locations further south. Within the natural temperature range of this species (− 1.8° to 5.5 °C), respiration rate data from both the present and previous studies were adequately fitted by a single Arrhenius regression (Q10 of 2.8), although South Georgia krill showed an upward deviation from this regression between 0° and 2 °C (the lower temperature range at South Georgia). Metabolic compensation (i.e. the comparative lowering of respiration rate) at the high temperatures experienced at South Georgia was not apparent, although the higher than predicted metabolic rates at low temperatures suggests acclimation of South Georgia krill to a warm water lifestyle. Weight-specific respiration rate was significantly higher in sub-adults and adults compared to juveniles, highlighting the metabolic burden of reproduction. South Georgia krill showed no further increase in respiration rate when exposed to acute temperatures (5.5–12.2 °C), indicating that they were already at the limit of aerobic capacity by 5.5 °C. Overall, this study shows that even small degrees of additional warming to South Georgia waters are likely to make conditions there metabolically unsustainable for Antarctic krill.last_img read more

BYU Women’s Volleyball Releases 2018 Schedule

first_img Tags: BYU Women’s Volleyball/Heather Olmstead/Marquette/USC/Utah Brad James Written by June 6, 2018 /Sports News – Local BYU Women’s Volleyball Releases 2018 Schedule FacebookTwitterLinkedInEmailPROVO, Utah-Wednesday, BYU women’s volleyball head coach Heather Olmstead announced the 2018 slate for her squad.Women’s volleyball in recent seasons is among the Cougars’ most successful athletic programs and Olmstead has given her team plenty of chances to test its mettle moving forward.BYU will face five 2017 NCAA Tournament teams in non-conference action including Stanford, Wichita State, USC, Marquette and Utah.The season officially starts August 24-25 at Durham, N.C. where the Cougars will face ACC foe Duke twice. The Cougars are 2-0 all-time against the Blue Devils.Next, they will have their home openers August 30-September 1 as they host the BYU Invitational. Among the Cougars’ foes in this event are traditional power West Virginia as well as aforementioned Stanford and Wichita State.On September 7-8, the Cougars will be in Milwaukee as participants in the Marquette Invitational where they will face Marquette, USC and Syracuse..The Cougars host in-state rival Utah September 13 before going to Ogden to face Weber State September 15.The Cougars will have senior day on November 10 when they host fellow West Coast Conference foe San Franciscolast_img read more

Scoreboard roundup — 7/9/18

first_imgJuly 10, 2018 /Sports News – National Scoreboard roundup — 7/9/18 FacebookTwitterLinkedInEmailABC News(NEW YORK) — Here are the scores from yesterday’s sports events:INTERLEAGUECincinnati 7,  Cleveland 5AMERICAN LEAGUEBaltimore 5,  N-Y Yankees 4Boston 5,  Texas 0Tampa Bay 10,  Detroit 9, 10 InningsN-Y Yankees 10,  Baltimore 2Oakland 2,  Houston 0Minnesota 3,  Kansas City 1NATIONAL LEAGUEN-Y Mets 4,  Philadelphia 3, 10 InningsPittsburgh 6,  Washington 3Miami 4,  Milwaukee 3, 10 InningsPhiladelphia 3,  N-Y Mets 1L-A Dodgers 8,  San Diego 2San Francisco 2,  Chi Cubs 1, 11 InningsCopyright © 2018, ABC Radio. All rights reserved. Written bycenter_img Beau Lundlast_img

Nick Diaz to fight in March after four-year absence from UFC

first_imgNovember 16, 2018 /Sports News – National Nick Diaz to fight in March after four-year absence from UFC Written by FacebookTwitterLinkedInEmailDavid Dermer/Diamond Images/Getty Images(NEW YORK) — Nick Diaz is returning to the Octagon after four years.The UFC welterweight will face Jorge Masvidal on March 2 in Las Vegas at UFC 235, according to UFC President Dana White.While contracts for the fight have not yet been signed, they are close to being completed, sources tell ESPN.Diaz last fought in January 2015 against Anderson Silva. While he lost the bout to Silva, the result of the fight was later changed to a no-contest after both fighters tested positive for drugs.Copyright © 2018, ABC Radio. All rights reserved.center_img Beau Lundlast_img read more

Watch college athlete find out she’s been awarded a full scholarship and tell her mom

first_imgToday, @albschaffer21 was rewarded for the unbelievable work she puts into our team! So proud of the example she sets for us each and every day! #signed #fullride #scholarship⁠ ⁠ @NCAAVolleyball @NCAA @AVCAVolleyball @espn @espnW @SunBelt @ULMWarhawks @ULM_Official pic.twitter.com/XFARrtKYg0— ULM Volleyball (@ULM_VB) January 15, 2019What Friedland’s team didn’t know was that he had availability for one more full scholarship for the spring, and when Schaffer read her note, it was much more than just words of encouragement.“You are and have been one of the most hard-working and dedicated players on this team,” the note read. “You are a great teammate and leader in this program. Today, your hard work pays off for the spring semester of 2019.”Schaffer covered her mouth in shock and fought back tears to get through the last sentence: “You’re going on full athletic scholarship. Congratulations.”“I kept clicking on the screen because I thought my phone was frozen,” Schaffer said. “My mom is never quiet, so that was new to me too. She was speechless.”Schaffer also called her dad who responded, “Oh, Albany! That is so awesome!”Her teammates yelled in the background of the calls, “Yeah, Albs! You deserve this so much!”“They were being the greatest teammates ever telling me how happy they were for me,” Schaffer said. “Everyone was coming up and giving me hugs.”“Albany is one of the hardest working players on and off the court,” Friedland said. “She’s very eager, hungry to learn and isn’t afraid of being challenged. She’s the teammate everyone knows has their back.”“I was working as a waitress in the offseason and trying to pick up shifts to pay rent. Even little things like books get expensive and a lot of times I’d have to share with someone,” Schaffer said. “With this scholarship, I can really just focus on volleyball and school.”More than just some of the financial pressure being off, Schaffer said this scholarship is the icing on the cake of a long time dream.“Ever since I was little it was my dream to play Division 1 volleyball,” Schaffer said. “I feel like I’m exactly where I need to be.”Congratulations and keep up the great work, Albany!Copyright © 2019, ABC Radio. All rights reserved. #NewProfilePic pic.twitter.com/c84xhSHUHj— Albany Schaffer (@albschaffer21) October 2, 2018Schaffer’s coach Russ Friedland had each player on his team draw a teammate’s name out of a hat and write them an encouraging note. They went around in a circle and read them out loud, saving Schaffer for last.What Friedland’s team didn’t know was that he had availability for one more full scholarship for the spring, and when Schaffer read her note, it was much more than just words of encouragement.“You are and have been one of the most hard-working and dedicated players on this team,” the note read. “You are a great teammate and leader in this program. Today, your hard work pays off for the spring semester of 2019.”Schaffer covered her mouth in shock and fought back tears to get through the last sentence: “You’re going on full athletic scholarship. Congratulations.” Beau Lund January 18, 2019 /Sports News – National Watch college athlete find out she’s been awarded a full scholarship and tell her momcenter_img Written by FacebookTwitterLinkedInEmailMatt_Brown/iStock(NEW YORK) — Christmas came a little late for a volleyball player at the University of Louisiana Monroe.Albany Schaffer, a junior walk-on on the ULM Warhawks volleyball team, thought she was attending a regular team meeting when she got a surprise that will change her life.last_img read more