Research News

[New publication] Mothers matter for the CO2 sensitivity of fish offspring

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28 November 2017. The Journal of Experimental Marine Biology and Ecology just published the latest study by our group looking at differences in the CO2 sensitivity of Atlantic silverside offspring stemming from different mothers. Congratulations to Jacob Snyder for his first peer-reviewed publication.

Among the highlights of the study:

  • Offspring produced by different females varied in their sensitivity to high CO2 conditions.
  • Specific fatty acids in eggs were correlated to the log-transformed CO2 response ratio of embryo survival and hatch length.
  • Maternal provisioning might be an additional determinant of CO2 sensitivity in fish early life stages.

Citation:

Snyder, J.T.*, Murray, C.S.*, and Baumann, H. (2018)
Potential for maternal effects on offspring CO2 sensitivities in the Atlantic silverside (Menidia menidia).
Journal of Experimental Marine Biology and Ecology 499:1-8

Fig2 - dancing men
M. menidia. Responses to high CO2 conditions among replicates within and among females: (A) embryo and larval survival; (B) overall survival; (C) SL at hatch; and (D) final SL (16 dph). Patterns of larval growth were nearly identical to panel D and are therefore omitted. Ambient and high CO2 treatments are denoted by red and blue colors, respectively. Small symbols depict replicate survival (A,B) or replicate average size (C,D), while large symbols depict CO2 treatment averages for each female. Black lines connect average response for each female. Asterisks represent significant differences (P < 0.05) between CO2 levels within offspring of each female (Bonferroni adjusted t-test). Letters denote to females A to E.

[Lab news] Baumann lab participates in Avery Point Open House Event

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Large-50th-Logo-white-background-3-e1484861299421
15 October 2017: All members of the Baumann lab – Hannes, Emma, Chris, Julie and Jake had fun at an Open House event at the Avery Point Campus as part of the 50th Anniversary celebrations. The whole department participated with a flurry of educational activities and fun exhibitions.
Our lab manned a table outside the Rankin Lab, telling people about the nearshore fish community, the phenomenon of ocean acidification and the measurement of pH in water. Everybody chipped in, thanks!
Hannes also premiered reciting Dr. Seuss’ “The Lorax” in front of young and old in the AP auditorium.

Check out some of the fun around the “Ocean Acidification and our fish” table:

ChrisTank
There are fish!
JakeandJulieTable
Jake and Emma assist a little scientist in measuring the pH in our two demonstration tanks

Menidia
Atlantic silversides from Mumford Cove, CT, swimming in our tanks. After the end of the demonstration, we released back into the wild.
RobMason
Prof. Rob Mason taking briefly over our display. Emerging topic apparently – Mercury and ocean acidification

SashaLuka
Fascinating sea life …

Lukaseastar
What an incredible creature a sea star is!
DrSeuss
Hannes recited “The Lorax” – Dr. Seuss classic, comic-poetic tale of greed and environmental destruction

JulieTableLizSister
Julie manning our Ocean acidification outreach table at the Rankin Lab on 15 Oct 2017

[Lab news] Measuring juvenile silversides. Live.

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10 October 2017. Today, Chris, Emma, and Julie measured over 400 juvenile Atlantic silversides for their length and weight. This time, however, we did not euthanize the fish before, but successfully measured them while still alive, only a little drowsy from the mild anesthetic we administered before.

Click on the video below to have a look for yourself.
Congratulations all, for a job well done!

[New publication] Nearshore pH and DO fluctuations across 16 US estuaries!

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October, 2nd, 2017: Happy to announce that Estuaries and Coasts just published (online) our article that looked at unifying principles of pH and DO fluctuations across many US nearshore habitats. The datasets belongs to the US Nearshore Estuaries Research Reserves System (NERRS) and is one of the most extensive monitoring datasets in coastal aquatic habitats. In this case, we used 15 years of continuous monitoring data (> 5 million data points) from 16 different reserves across the US Atlantic, Caribbean, Gulf of Mexico, and Pacific coasts and analyzed short- to long-term variability in pH and DO fluctuations. Among the highlights:

  • Our analyses confirmed that large, metabolically driven fluctuations of pH and DO are a unifying feature of nearshore habitats. Even more so, we were able to show that across habitats, one can predict mean pH or mean diel pH fluctuations simply based on salinity and oxygen levels/fluctuations. This provided strong empirical evidence that common metabolic principles drive diel to seasonal pH/DO variations within as well as across a diversity of estuarine environments.
  • As expected, there were no interannual, monotonic trends in nearshore pH conditions; instead interannual fluctuations were of similar magnitude than the pH decrease predicted for the average surface ocean over the next three centuries.
  • By correlating weekly anomalies of pH, oxygen, and temperature, we found strong empirical support for the notion that coastal acidification — in addition to being driven by eutrophication and atmospheric CO2 increases — is exacerbated simply by warming, likely via increasing community respiration.

Citation and link:
Baumann, H. and Smith, E. (2017) Quantifying metabolically-driven pH and oxygen fluctuations in US nearshore habitats at diel to interannual time-scales Estuaries & Coasts (published online 2 Oct 2017)

Baumann-&-Smith-ESCO_Fig6
Among many other aspects, the paper analyzed interannual trends in temperature (red bars), dissolved oxygen (%, blue bars), and pH (green bars) at 16 US Nearshore Ecological Research Reserves (NERRS), shown as yearly anomalies derived from averaging monthly anomalies for each variable, site, and year. Black trend lines were derived by LOESS smoothing.

[Lab news] Group effort – starting new silverside experiments in June 2017

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It’s the beginning of June, and in the Baumann lab that means: high time for experimental research on the Atlantic Silverside, the famous forage fish and important model species! This year, we have several major objectives; our NSF-sponsored research examines the sensitivity of offspring to the individual and combined effects of high CO2 and low oxygen (Chris Murray), while in collaboration with our colleagues from Cornell University we rear several families for genetic and transcriptomic studies. Elle Parks, our REU student just started her work on the effects of CO2 and temperature on the starvation resistance of silverside larvae. As always, the days when new experiments start are a group effort, where everybody including many volunteers help. Thanks to Peter Morenus (UConn) for the coming down for documenting the activities!

This story is also featured on UConn Today.

[Field work] To Georgia and back in 48h – a special road trip for science

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By H.B.

Somewhere after Richmond, VA, the sun sets and traffic on the I-95 begins moving better. At long last. The four people in the burgundy Dogde Challenger have all already cycled through their driving shifts once and dare an impatient glance at the time left. Still more than 8 hours. More than 8 hours to reach this very special location at the Atlantic coast – Jekyll Island, Georgia. In the trunk of the car a jumble of coolers and a beach seine, buckets, air pumps, and hoses topped with the crumpled witnesses of roadside dining. This is no ordinary road trip.

We, that are Aryn and Nicholas from the Therkildsen lab of Conservation Genetics lab at Cornell University and James and Hannes from the Fish Ecology Lab here at UConn; we went on this road trip to catch live, spawning ripe Atlantic silversides from the southern edge of the species distribution. We then intended to bring these fish back to UConn alive, sample another population from the south shore of Long Island (Patchogue, NY) and produce genetic crosses of these populations.

The broad goal of our expanding collaborative efforts with our geneticist friends from Cornell is the creation of an annotated genome of this species, which will be an important milestone in deepening or understanding of the molecular and genetic responses of organisms to local selection regimes and marine climate change. Given the Atlantic silverside’s ecological importance as an abundant forage fish along the American east coast and it’s rich history as a model organism in evolutionary and ecological studies, the annotated genome is the next logical step.

Even at hindsight, the plan still seems a little insane. But it worked. We indeed managed to catch spawning silversides at the Georgia site and then transported them immediately back to our Rankin Lab, which involved another 17 hours of driving back. After securing samples from Patchogue, we indeed managed to cross single parents from each site to produce full-sib crosses that will later be used to produce what geneticist call a linkage map. Other across and within-population crosses will be used to study gene expression at two different temperatures or raise adults for producing an F2 generation.

The silverside larvae are currently well, feeding, and growing up nicely. We all cross fingers for this enterprise to end in good samples and a step forward for genetic studies on a marine fish.

[Field work] Our sand lance research in the news

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NOAA sanctuaries just published a little blurb online, introducing sand lance and it’s importance to the Stellwagen Bank National Marine Sanctuary, including a small section on the current research efforts funded by NOAA Regional SeaGrant.

“To that end, the team is collaborating with scientists from the University of Connecticut (UConn). UConn study members transport live-caught sanctuary sand lance to their lab, where further generations of sand lance are raised. The resulting larval sand lance are raised in high-tech rearing facilities that can be adjusted to mimic future ocean conditions.”

Sandlance laughing gull
Seabirds, sharks, seals, whales and more rely on sand lance as a food source. Here, a laughing gull munches one of these eel-like fish. Photo: Peter Flood

The entire article can be accessed by clicking on the link below
http://sanctuaries.noaa.gov/news/jan17/sand-lance-stellwagen-bank.html

[Field work] Sand lance spawning season has started

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4th time’s the charm: sampling spawning ripe sand lance on Stellwagen Bank

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On 2 Dec 2016, the sun rises over Scituate, MA, harbor and the fishing trawler that will take us to Stellwagen Bank this time.
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On 2 Dec 2016, Chris waits for the action to start, while the trawler is leaving Scituate Harbor
sandlance embryos
Sandlance embryos, 24h after fertilization. The embryo stage in this species can be up to two months!
Early morning on 2 December 2016, we left Scituate, MA, for the forth time this year, heading towards Stellwagen Bank in search of spawning ripe Northern sand lance (Ammodytes dubius), a winter spawning forage fish of great importance to the Stellwagen Bank National Marine Sanctuary and the object of latest research efforts. While during the last three cruises in late October and November, we saw a progression of ripening in the specimens, up to now we didn’t actually find spawning ripe individuals. Today, though, things are different, and when the first sand lance appear in our beam trawl, we immediately know that today we’ve been at the right time and at the right place.
It seemed an ambitious dream not too long ago, but now we’re happy report that we’ve started an experiment on sand lance embryos in our lab. Thanks to Chris Murray, David Wiley, Mike Thompson, captain Steve and his deckhand Matt for the successful trip!
scituate-panorama-sunrise
Early morning low tide at Scituate Harbor on 2 Dec 2016. The calm is deceiving; outside of the harbor the sea is pretty rough

Check out some footage of the trip and the beam trawl operation on board of captain Steve’s fishing vessel

[Field work] Catching sand lance on Stellwagen Bank

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On 27 October 2016, Hannes, Chris and Julie joined researchers from the Stellwagen Bank National Marine Sanctuary (David Wiley, Anne-Marie Runfola, Brad Cabe, Michael Thompson), the USGS (Page Valentine, Dann Blackwood) and the crew of the R/V Auk (Dave Slocum, James Stasinos) to embark on our first of five total sampling missions in this enigmatic marine habitat. Our goal, catching live Northern sand lance, Ammodytes dubius, the so critical forage fish species that is referred to as the “backbone of the sanctuary”, because all kinds of marine predators from whales to tuna to seabirds gather on the bank to feast on them.

Our renewed efforts are part of our recently funded NOAA Regional SeaGrant Project to investigate the effects of ocean warming, acidification and low oxygen on sand lance early life stages.

As before, we first started by deploying a Seaboss sediment grab, which allows our colleagues from the USGS to characterize sediment types in association with the occurrence of sand lance. In addition, however, we brought a small beam trawl along for the first time to find out, whether we could more effectively catch sand lance and then transport them live to our seawater facility at UConn Avery Point. We are happy report that the efforts by all have paid off and that there are now ~ 180 adult ripening sand lance swimming in our tanks. Thanks all, see you again for the second survey in a few weeks!

Check out the video below, made from clips of no less than five different GoPro’s (if you listen carefully, around 2:40 into the clip you’ll hear the singing of some nearby humpback whales):

[New publication] Long-term growth consequences of acidification in Atlantic silversides

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October 10th 2016 was a special day for our still young lab here at the University of Connecticut, Today, the ICES Journal of Marine Science published the paper of Chris Murray et al., which is the first of hopefully many publications of our experimental findings originating out of our new laboratory facility here at UConn Avery Point.
Chris and his co-authors report on a large-scale, quantitative rearing experiment on Atlantic silversides eggs, larvae and juveniles under contrasting CO2 conditions that took place between May – September 2015. This novel experiment was designed to address three critical issues lacking in previous ocean acidification research on fish. First, the study spanned several ontogenetic stages. Second, it used very large numbers of individuals to robustly characterize not just potential shifts in mean responses, but also changes in the distribution of length, weight, and condition factor. Third, it provided food at standardized, non-excess levels to prevent that potential metabolic costs of high CO2 exposure could be compensated by survivors simply by eating more food.
Overall the study demonstrated seemingly small but significant growth reductions due to high CO2 and identified a small number of fatty acids that were of significantly different concentrations in high vs. control juveniles.

murray-etal-ijms2016_fig3
Distributions of condition factor per 2mm TL interval for juvenile M.menidia reared for 122dph at control (a) and high CO2 conditions (b). Thick and thin black lines correspond to the 10th/90th and 25th/75th percentiles, respectively, while the red line depicts the median. Data below the 10th and above the 90th percentiles are depicted by black dots. Underlying grey bars show relative frequencies for each 2 mm TL class. Black and grey numbers correspond to numbers of individuals measured for both TL and wW, or for TL only, respectively.
murray-etal-ijms2016_fig4
Cumulative frequency distributions of (a) total length (TL) and (b) wet weight (wW), in juvenile M. menidia reared for 122 dph at control and high CO2 conditions.

Murray, C.S.*, Fuiman, L., and Baumann, H. (2016)
Consequences of elevated CO2 exposure across multiple life stages in a coastal forage fish.
ICES Journal of Marine Science (published online 10 Oct 2016)