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We Monitor “What” in the Water?

Written on: August 15th, 2018 in Blackbird Creek ReserveEducation & OutreachResearch

An experience that is avoided by most college students became the beginning of a morning adventure… I was up before the sun; a rarity in itself. I had risen from the depths of my room to explore the waters of Blackbird Creek on a nekton trawl. The word nekton was absent from my vocabulary prior to this summer. Yet, within the first week of my internship I was gladly informed that nekton are any aquatic organisms that actively swim. Immediately intrigued by this foreign concept, I wanted to further my understanding and asked to join one of these so called “nekton trawls.”

I was later informed of an opportunity to assist Michael Mensinger and Drew Faulhaber on one of their monthly surveys. On August 6th, that fateful morning came and I was inquisitive as ever. Various questions flowed through my mind and I pondered: How does a trawl even work? What kind of data are we collecting? Why is this data important?” Although, all of my contemplations were soon contented when we set off and I was able to experience all of these things first hand.

Mike Mensinger and Drew Faulhaber measuring a striped bass.

The Blackbird Creek has been segmented into seven distinct zones based on salinity, then a randomized GPS point is selected within each zone.  The GPS point marks the place to begin the trawl. It is important to note that trawling is a method of fishing where a net is driven open by wooden boards, known as otter boards and runs along the bottom to collect various bottom-dwelling organisms. Setting up the trawl and driving the 22 foot motorized boat fell onto the two men I accompanied, while my job was to record start & end times and GPS coordinates. After reaching 300 meters in distance the trawl was lifted from the water and the captured organisms were placed into a fish processing bin. Once they were measured, and the data was recorded they would be returned to the water. Finally, before progressing into the next zone water quality and creek depth measurements were recorded.

Although this seems like a straightforward procedure, there is always room for mistakes to happen. During trawling in one of the zones, the net became caught and ripped from unknown debris residing at the bottom of the water way. The largest lesson to be learned from the entire situation is that scientists and people alike need to have the adaptability to overcome obstacles. Mr. Mensinger took this set back with a level head and having planned ahead was able to fix the net and continue the survey.

As we continued and eventually came to a close, it became evident that the high abundance of animals of this month were: white perch (Morone americana), hogchokers (Trinectes maculatus), channel catfish (Ictalurus punctatus), and blue crab (Callinectes sapidus). The data collected this month appears to be relatively consistent with Michael Mensinger’s  data collected last year, with the most abundant species being white perch, hogchokers, weakfish (Cynoscion regalis), and blue crabs (Mensinger, 2018).

A hogchoker caught during the trawling survey at Blackbird Creek on August 6th.

By comparing the data between the months and years a clearer picture of the area’s short-term and long-term biodiversity and biodiversity changes will become clearer, which helps scientists understand the effects of climate change and other forces on the nekton community. I am appreciative of Delaware’s National Estuarine Research Reserve for presenting me with a new perspective and the skills to match so that I may one day be able to improve society’s understanding of nature… and also for helping me get me up before the sun rose.

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Mensinger, M., 2018. Monitoring Nekton Biodiversity in Blackbird Creek. Report – submitted to the Delaware National Estuarine Research Reserve, Dover, Delaware.

Written by Jared Ryan, 2018 Environmental Education Intern.



DNERR’s Tree Swallows and Bluebirds Need YOU

Written on: July 11th, 2018 in Blackbird Creek ReserveEducation & OutreachSt. Jones ReserveVolunteers

DNERR’s Tree Swallows and Bluebirds Need YOU

Spring is here, and the St. Jones and Blackbird Creek Reserves have sprouted a number of mysterious, wooden boxes affixed to PVC poles. Where did these boxes come from? And why?

At the Blackbird Creek Reserve, a nest box is clearly marked as being monitored by DNERR. Photo: M.L. Christmas

With such questions in mind, this writer approached Christina Whiteman, DNERR’s Environmental Scientist and Stewardship Coordinator, and Kari St. Laurent, DNERR’s Research Coordinator. Here is what they said; and you, the readers of this blog, can volunteer to be in on the fun!

What is the purpose of the nest boxes? Are they for Wood Ducks? Or Bluebirds? Or just what? Christina responded, “They are for the use of cavity‑nesting birds, such as Eastern Bluebirds and/or Tree Swallows, for breeding and brooding purposes.”

Why the PVC posts? Aren’t they typically wood? “That is a strategy being tried for avoiding the incursion of predators, like snakes. Snakes cannot easily climb PVC, unlike when the traditional, wooden posts are used.” (One can certainly imagine why a snake and a nest box full of eggs or chicks is not a good mix.)

It’s “problem solved,” then, with PVC! “Not exactly. One ongoing problem we have is House Sparrows, a species that often takes over nest-box spaces and crowds out the other species. We are still trying to devise strategies for deterring them.”

 So, people are an important part of the equation? “Yes! Some human involvement is needed: for monitoring the nest boxes and documenting the avian activities.”

A line of nest boxes at the ready at Blackbird Creek Reserve, just a portion of those on the premises. Photo: M.L. Christmas

This writer did not need to inquire where this help was needed. She had been at the Blackbird Creek Reserve earlier in the week and had noticed a number of nest boxes throughout the complex, including a sweeping array in the Reserve’s “back 40”; and on the way to this interview, she also saw a line of nest boxes at the St. Jones Reserve.

So, what specific type of help is needed, and how is it accomplished? Christina showed this writer an amped-up, angle-y, oversized, dental-mirror-like thingy that is used for peering into the nest boxes without disrupting the inhabitants. Any Philadelphia-area folks familiar with Elfreth’s Alley would liken the implement to a “Busybody Mirror,” a Colonial-era device attributed to Benjamin Franklin. That specialized type of mirror, still being sold today, allows a homeowner on the second floor of a home to discreetly view who is calling at the front door. This is similar, but in reverse: allowing the nest-box checker, when standing at the “front door” of the nest box, to peer inside without disturbing the avian occupants.

Can anyone participate? “Yes, and the nest boxes are also an ongoing research-intern project. The training in the proper protocol is provided via the Cornell Lab of Ornithology’s NestWatch program. The database tracks the location of a nest box and which species is using it. We have been monitoring our boxes at DNERR for two years. Our interns and volunteers can become certified in nest-box monitoring, and they help monitor the boxes throughout the summer. We also have a partnership with Delaware State University [for monitoring the boxes at the DNERR], and Del State bands the Eastern Bluebirds that are in our boxes.”

How has that been going? Any discoveries? “They have been banding some of the birds to see who comes back or to determine if they are overwintering.

A peek inside a nest box to check on its precious occupants: Babies on board! Photo: Molly Williams, EPSCoP research intern from 2016.

We start checking the nest boxes, and scouting the arriving birds for color‑coded bands, in April. That was when, the other year, we learned of a female Bluebird, at the Blackbird Creek Reserve, laying white eggs. They were lacking the normal light-blue pigmentation. A small percentage of Bluebirds have white eggs, and the interns from Del State banded the chicks that hatched from those particular eggs, for the purposes of future monitoring.”

What else is needed, apart from human assistance — or should that be “assistants”? “We would like to get more Bluebirds at the St. Jones Reserve, though we might not have quite the right environment for them here, as we do at Blackbird Creek. Here at the St. Jones Reserve, the conditions are good for Purple Martins. We have found that the houses with the crescent-shaped openings work best here. We had been trying to attract Purple Martins, with mixed results in the past, but were not fully successful until last year.”

Bottom line for the readers of our blog? “We would like to get some volunteers involved with the monitoring process and with helping clean out DNERR’s nest boxes in the fall. The Cornell Lab of Ornithology’s NestWatch website contains a lot of helpful information,” Christina said.

Kari St. Laurent remarked, “One of the things I like best about the Cornell Lab’s nest-box program is that participants can be certified in monitoring and then take home the ‘recipe’ [for maintaining nest boxes in their own yards]. It is something that people of all ages can do. I know of a research paper from about two years ago that used NestWatch data about Tree Swallows. That is an example of how citizen-science projects, such as these, can be useful for others’ research.”

Christina then noted that anyone “can see the real-time data at the Cornell Lab of Ornithology’s NestWatch site: <https://nestwatch.org/>.”

Baby birds: What’s not to love? Photo: Kathleen Carey, conservation intern from 2016.

Kari continued, “Nest-box monitoring is ‘warm and fuzzy’ — but is also very important. As mentioned, we can fold this data into other research projects. We even studied the effect of emptying most of the boxes but leaving a few old nests in others. Would the birds have a preference, when selecting a box for the new season, between an empty box or using one containing a nest left over from a previous brood? Would the existence of the old nests help or not? It turned out the preference was really for where a box was located — adjoining the meadow at Blackbird Creek, as opposed to being closer to the woods — and not whether a nest was already in place inside a particular box. Of course, we always need more data before we make conclusions.”

This guest-blogger could not help but mentally make the correlation that, just like the real-estate-agent adage, even for Bluebirds the key to a property’s success is “location, location, location”!

And to further anthropomorphize: Who can look at these baby-bird photos provided by past DNERR interns and not think “Cootchie-cootchie-coo”? Adorable, yes, but the nestlings are also an important part of our ecosystem. Who knew citizen science could be so cute?

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Text by M.L. Christmas; photo credits as noted.

M.L. Christmas, MSM, is a freelance writer/editor living in the Dover area. She is a longtime member of Delaware Press Association and the National Federation of Press Women.


DNERR Summer Interns!

Written on: June 19th, 2018 in Coastal Training ProgramEducation & OutreachResearchSt. Jones Reserve


The DNERR staff would like to welcome the helpful hands of our summer interns!  This group is eager to get to work and learn the tricks of their trade.  We are all looking forward to a fun, educational, and fantastic summer!

Jared Ryan – Education Intern

I am currently a sophomore at the University of Delaware and plan on graduating in the fall of 2019! I am pursuing a double major in Wildlife Ecology and Conservation, as well as Agriculture and Natural Resources. I am the Education Intern under Maggie Pletta, Education Coordinator.  I have always enjoyed wandering through nature and learning about the unique intricacies that allows for an ecosystem to thrive. Generally, I fill my time with exploration of surrounding parks and photography of the flora and fauna within. I one day hope to educate the public of the importance of conservation and how connecting with the earth can change a life for the better.



Mike Snyder – Policy and Communications Intern

Hello, all.  I received a BA in Political Science from Millersville University in 2008, and a JD from Villanova University in 2012 with a focus in Environmental and Energy law.  I am a Policy and Communications Intern under Kelly Valencik, Coastal Training Program Coordinator.  I am an avid golfer and Pittsburgh sports fan.  I also love to hike, climb, birdwatch, and take long walks on the beach.  For that matter, I enjoy walks on the beach of any length.  I hope to save the world, one wetland at a time.  And in the meantime, I look forward to getting know all of you.





Annette Carlson – Research Intern, Hollings Scholar

My name is Annette Carlson; I am a senior at Humboldt State University in Arcata, California. I plan to graduate in the spring of 2019 with a Bachelor’s of Science in Oceanography and a minor in Geology. In my free time I like to hike or go to the beach and play Frisbee with my dog, Venus. I enjoy traveling and experiencing how other people live, I think it helps me grow as a person. At the Reserve, I am a research intern through the National Oceanic Atmospheric Administration Hollings Scholar program, under Kari St. Laurent, Research Coordinator. While I’m here, I’ll be looking at carbon stock and how it changes with sediment depth. I’m still evaluating my options on whether I want to attend graduate school or enter the work force after I graduate from Humboldt State. No matter where I end up, I hope to be working toward a better future for humanity and our planet through scientific study and conservation.


Ewan Malenfant – Research Intern 

My name is Ewan Malenfant, I attend Allegheny College with a major in Environmental Science and a double minor in Physics and Astronomy.  I plan to graduate in 2020. This summer I am the Research Intern under Christina Whiteman, Stewardship Coordinator, and Drexel Siok, Environmental Scientist.  My hobbies and interests include tennis, playing the drums, backpacking, and just about any outdoor recreational activity imaginable.  My life goal is to live in the mountains doing environmental science research and field work.  I am most passionate about human environmental impacts, getting off the beaten track, and the complexities of the universe. I’m very curious and always trying to broaden my knowledge.  


Sydney Hall – Research Intern

My name is Sydney Hall, I am a senior at Wesley College studying Environmental Science.  I am a DNERR research intern under Mike Mensinger, Environmental Scientist.  I am looking forward to this experience to gain knowledge about various projects and hands-on experience in the field and the lab.  This opportunity will give me a strong perspective on what a future career in environmental science could be like.  During my free time, I enjoy spending time traveling with my family.


Yay! Fishies Again!

Written on: May 8th, 2018 in Education & OutreachGuest BlogSt Jones Events and ProgramsSt. Jones Reserve

DNERR always offers something unexpected, and recently, one needed only to look overhead to see it. In the lab at the St. Jones Reserve, dual clotheslines were strung with, no, not freshly laundered lab jackets or drip-drying dip-nets, but damp sheets of colorfully daubed paper. The sheets overflowed onto many of the nearby horizontal surfaces.

Though I had already experienced Gyotaku, the Japanese art technique known as fish printing, this guest-blogger did not realize DNERR offers different fish-printing opportunities for the smaller fry among us. The large, rubber fish used by teens and adults can be too much for little hands, I was told, and hence these smaller fish-print stamps.

I eyed the array of creatures — who, in turn, looked right back at me — and found the smiling jellyfish irresistible for its quirky, almost paradoxical combination of hidden danger and overt insouciance.

Headlines in late 2017** announced that a University of Delaware professor, along with a UD grad who’s a researcher at the Smithsonian Institution’s National Museum of Natural History, discovered that a type of jellyfish in our region that has long been thought a single species is in fact two: the U.S. Atlantic Sea Nettle (Chrysaora quinquecirrha) and the Atlantic Bay Nettle (Chrysaora chesapeakei). The moral of that story? Even for the experts, there is always more to learn about this big world around us.

The moral of this story? Whether one species or two, those jellies would not take kindly to being dipped in paint and then pressed onto blank art‑paper; so the child-friendly stamps are a great way for kids to interact with these particular marine denizens without incurring “The Wrath of the Chrysaora,” a type of 3-D, sensory, theatrical experience no one wants to have — the jellies included.


** For more information:





Text and photos by M.L. Christmas

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M.L. Christmas, MSM, is a freelance writer/editor living in the Dover area. She is a longtime member of Delaware Press Association and the National Federation of Press Women.


Dancing with Horseshoe Crabs, Under the Stars

Written on: March 27th, 2018 in Education & OutreachGuest BlogResearchVolunteers

Do you recall the mention, in this blog, of the “poetry in Horseshoe Crabs”? (If not, just keyword-search “poetry” on this page.) Now is your chance to prepare for experiencing that poetry for yourself, when “dancing” with the crabs during a real-life beach “party” in support of a good cause: DNERR’s annual Horseshoe Crab Spawning Surveys.

DNERR has several upcoming Horseshoe Crab Survey Training Sessions, in advance of the actual surveys that will be conducted from late April through early July. This year’s training sessions are:
Saturday, April 7:  10 am – Noon, and 2 pm – 4 pm
Further details can be found by clicking here.

Scene from a late-night beach “party” in Delaware: “Dancing” with the Horseshoe Crabs, under a canopy of stars. (Photo: Drexel Siok)

Signing up for a training session, and then being a participant in a count, are great ways for everyday citizens to assist with the advancement of science!  Participating in a Horseshoe Crab Survey is an opportunity to attend a special type of late-night “party” on the beach, at high tide, and to have the privilege of “dancing” around the spawning Horseshoe Crabs while standing under a canopy of stars. Each group uses a portable quadrat for a “dance floor,” its boundaries delineated with a framework of PVC piping. 

This guest-blogger crossed paths recently with DNERR’s Horseshoe Crab Spawning Count Coordinator, Drexel Siok, and with DNERR’s Research Coordinator, Dr. Kari St. Laurent, for the purposes of learning more about the program. Drexel has been coordinating the counts, he said, for about five years.

“We always need new people to help out; but those who have previously completed the training must still come back every three years in order to stay current with procedures.” He continued, “Right now, we are looking for 75 people to participate in the training sessions. The registration for the sessions is done online.”

Kari, noted, “Some of the volunteers come from a distance, such as New England; so they are not necessarily all local people.” Clearly, all are driven by a love for the cause. “We also get a decent amount of school kids, of middle-school and high-school students.”

The training sessions typically cover topics such as biology and management, and they address such questions as why conduct the surveys, who uses the data, and what can — and cannot — be inferred from the data. Drexel and Kari agreed that, “Drawing accurate inferences is not that easy.”

Horseshoe Crab shell affixed with a USFWS tag, used for illustration purposes at the St. Jones Reserve. (Photo: M.L. Christmas)

“For instance,” Drexel explained, “Horseshoe Crabs reach full maturity at 8 years. That is the point at which they start to come up on the beach. So any changes to harvesting policies might not show up for a while in the count data. The spawning survey is also a measure of just the crabs we can see on the beach, and not necessarily the entire population.”

Kari added, “That is also why it is important to look at whole Delaware Bay-wide picture, not what is happening at just one point, on one particular beach, in Delaware.”

As an enticement to would-be survey-participants, she cited the fact that, “The U.S. Fish & Wildlife Service has a Horseshoe Crab tagging program. Watch for those tags! If you spot one on a crab, and report its number, you can receive a pin [as a prize].”

Drexel noted, “Hundreds to thousands of Horseshoe Crab tags are affixed per year. We have seen maybe 10 or 15 total in our surveys.” It pays to be observant, and therefore DNERR’s having the extra pairs of human eyes out there is important in more ways than one.

“We need a significant amount of people each night of a count,” Kari noted. “Otherwise, that is a data gap we can never get back. We really rely on our interns and volunteers for assisting with these counts.”

Can we rely on YOU to help? Please let us know!


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Text by M.L. Christmas; photos by Drexel Siok and M.L. Christmas, as noted.

M.L. Christmas, MSM, is a freelance writer/editor living in the Dover area. She is a longtime member of Delaware Press Association and the National Federation of Press Women.