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.
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:
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!
October, 2nd, 2017: Happy to announce that Estuaries and Coasts just published (online) our article that looked 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 analyses 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 provides 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 are no monotonic trends in nearshore pH conditions, but interannual fluctuations that are 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 to 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.
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!
Hydrated, ready to be fertilized eggs extrude from a running ripe female Atlantic silverside when putting gentle pressure on the abdomen. (Photo: Peter Morenus, UConn)
Screens with enumerated embryos are suspended in each rearing container using fishing line. (Photo: Peter Morenus, UConn)
Hannes shows Elle Parks (REU 2017), how individual screen with enumerated embryos are suspended into the replicate rearing containers. (Photo: Peter Morenus, UConn)
On 9 June, Elle and Julie strip-spawn Atlantic silverside females into spawning dishes covered in window screen for eggs to attach. (Photo: Peter Morenus, UConn)
Chris and Jake strip-spawning. (Photo: Peter Morenus, UConn)
All adult silversides used to produce new offspring are getting measured and preserved. (Photo: Peter Morenus, UConn)
The Baumann lab, June 2017: from left to right; Isaiah Mayo, Julie Pringle, Chris Murray, Elle Parks, Hannes Baumann, Jacob Snyder, James Harrington + "Bear". (Photo: Peter Morenus, UConn)
Chris Murray inspects a screen with newly fertilized Atlantic Silverside embryos, prior to starting a new set of experiments. (Photo: Peter Morenus, UConn)
On 9 June 2017, members of the Baumann lab all help to start a new set of experiments in the Rankin Lab at UConn Avery Point. From left to right: Julie Pringle, Hannes Baumann, Elle Parks, Jacob Snyder, James Harrington, Isaiah Mayo, Chris Murray). (Photo: Peter Morenus, UConn)
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.
Adult silversides from Jekyll Island, GA, swimming in our holding tanks in the Rankin Lab at UConn
Andrew's Beach on Jekyll Island, GA, on 11 May 2017.
A newly hatched silverside larvae with a twist. It's a haploid specimen, produced by fertilizing eggs with UV-treated sperm.
James Harrington carefully replacing water in the transport coolers for the fish. All fish survived the transport.
The daunting view of the road trip on 10 - 12 May 2017. 34h of driving and way too little sleep in just two days.
On the morning of 11 May 2017, our old beach seine is drying on the beach park of Jekyll Island, GA. After its last successful trip, the 9 year old gear has now been retired.
The Jekyll crew Hannes, James, Nicholas, and Aryn (from left to right)
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.”
4th time’s the charm: sampling spawning ripe sand lance on Stellwagen Bank
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!
Check out some footage of the trip and the beam trawl operation on board of captain Steve’s fishing vessel
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):
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.