Biological Monitoring for MoCo

Field Reports from Department of Environmental Protection Staff

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  • Photos of Critters in Our Backyard in Montgomery County, MD

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Rapidfire Fish ID

Posted by mocobio on August 20, 2009

How many distinct fish species do you think there are in Montgomery County? How many do you think you could identify by sight?

County biologists have documented more than 60 species of freshwater in Montgomery County streams. They commonly encounter upwards of 25 different species (comprising more than a thousand individuals) during summer fishing surveys at a healthy stream site.  In contrast, at poor quality stream sites they may only find 1–2 species and low numbers of individuals.

Example of five different species of fish. From top to bottom: river chub, rosyface shiner, swallowtail shiner, spotfin shiner, and silverjaw minnow. Can you see the differences?

Example of five different species of fish. From top to bottom: river chub, rosyface shiner, swallowtail shiner, spotfin shiner, and silverjaw minnow. Can you see the differences?

It takes special background and skill to properly and efficiently identify freshwater fish.   Staff training and experience helps in identifying species by examining body shape and type, mouth orientation, finnage, coloration, and overall size. Occasionally, a biologist will need to carefully count scales or fin rays to distinguish one species from another.  Biologists check each fish for anomalies such as parasites, deformities, or signs of illness. If a question on fish identification or anomaly type arises, multiple biologists examine the specimen to come to a consensus. Published fish identification keys can be consulted when necessary.  If a consensus cannot be reached in the field, the fish is taken back to the laboratory so that key features can be examined under a microscope.

A yellow bullhead catfish, distinguished by its fin shape and yellow bottom whiskers (also known as barbels). A brown bullhead looks similar but has all brown whiskers. This one has ulcers in its mouth which would be noted as an anomaly. He looks happy nonetheless.

A yellow bullhead catfish, distinguished by its fin shape and yellow bottom whiskers (also known as barbels). A brown bullhead looks similar but has all brown whiskers. This one has ulcers in its mouth which would be noted as an anomaly. He looks happy nonetheless.

With fish sampling, speed is of the essence. Two important indicators of stream health are species diversity and biomass (total weight of the biological sample).  Once the total biomass of the fish sample is recorded, fish are quickly transferred to nets and placed in a bucket with a bubbler. It is important that the fish get enough oxygen while they wait to be processed.

Buckets with aerators provide oxygen to fish as they wait to be counted.

Buckets with aerators provide oxygen to fish as they wait to be counted.

Large individuals are typically processed first or transferred to their own bucket or live well (a bucket or other container with holes to allow water to flow through). If a fish individual is able to survive and grow large in a stream or river, it means that all of its needs are being met and even exceeded. Some large and long-lived species, such as brown trout, have very specific habitat and water temperature requirements. Thus finding a large individual frequently means that the stream is healthy enough to support them well as other age classes.

These two individual fallfish from the Little Paint Branch watershed represent different age classes indicating that this stream is supporting longevity and reproductive success in this population.

These two individual fallfish from the Little Paint Branch watershed represent different age classes indicating that this stream is supporting longevity and reproductive success in this population.

When we handle fish to identify them, it is important that our hands are wet to minimize damage to their scales and fins. Typically, it is acceptable to hold a fish out of the water for brief periods at a time to get a clear look at its key features. Sometimes it is helpful to put the fish in a plastic ziplock bag with water to examine for longer periods. Digital photos help us to document fish species and their identifying features to reference later.

A handful of fish to identify.

A handful of fish to identify.

Biologists call out fish species counts and any observed anomalies to another crew member who tallies and calls back to verify the information as we go.  (This is similar to the process used to place coffee drink orders at a Starbucks coffee bar with a long queue of customers). Using this approach, we identify accurately but rapidly, and get fish back into the water to reduce their stress.  At our most diverse and populated fish sites, it can sometimes take up to two hours to count and identify all the fish collected in the buckets.

Biologist and interns processing fish. Fish are counted, identified, recorded on the data sheet, and then released back into the stream.

Biologist and interns processing fish. Fish are counted, identified, recorded on the data sheet, and then released back into the stream.

 Additional Resources:

Fish Anatomy: EPA Resource on the Basics of Fish Anatomy

Freshwater Fish Identification Key: MD Department of Natural Resources technical key for identifying Maryland freshwater fish.

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Posted in Fish | 2 Comments »

Tools of the Monitoring Trade

Posted by mocobio on July 27, 2009

On fish monitoring days, we all meet early in the equipment room.  Gathering equipment takes about one hour each time we go out into the field.  Without equipment organization and meticulous planning, monitoring would be haphazard.  With so many people depending on our results, equipment calibration becomes an important part of the quality assurance process that provides reliable date from our monitoring procedures.  Cleaning equipment is an equally important process to ensure that our samples are correct, but also to ensure that we don’t introduce disease, alien exotics, and bacteria into the environment we are sampling in.

In all, there are 53 items we need to bring into the field on fish monitoring days.  The items range from data sheets to more complicated equipment such as our hydro lab and electro shockers.  Some of the equipment includes:

Buckets: After capture, the fish, crayfish, and salamanders are placed into buckets until they are identified and inventoried.  The buckets are oxygenated with bubblers to minimize trauma to the animals.

Bubblers: These portable oxygenating units are similar to those found in common aquariums.  Their purpose is to provide an oxygen-rich environment for the creatures while they await identification and weighing.

DEP employees use buckets with bubblers to hold fish temporarily while identifying and classifying.

DEP employees use buckets with bubblers to hold fish temporarily while identifying and classifying.

Data Sheets: These documents are where we store information obtained on site.  Every detail is documented including habitat conditions, water chemistry, and lists and quantities of species  found at the site.

Block Nets: Two large floating nets are placed across the stream’s cross section and are separated by 75 meters.  The nets help to contain a specific section of stream, known as the stream work station.  The biological specimens within this area can’t escape up or downstream.

A block net is set up to define the bounds of the sampling site.

A block net is set up to define the bounds of the sampling site.

Digital Scale: We use the scale to measure the biomass or collective weight of all the fish captured.  If a stream has a low biomass, it can be an indication of poor stream health.

A digital scale is used to weigh a fish found in sampling.

A digital scale is used to weigh a fish found in sampling.

Electro Shockers: This piece of equipment is worn as a backpack.  It operates off a battery similar to that used in automobiles.  The voltage used depends on several factors including the size of the fish, the depth and width of the stream, and the water’s electrical conductivity.  The voltage range is typically between 100 and 500 volts.  We submerge the anode, a long hand held pole, into the water and run an elecetric pulse through it.  This stuns the fish without killing them.  They float to the surface, where we collect them in nets and place them in temporary holding buckets for sampling.

While one field tech uses a shocker to stun the fish, the other captures them in her sampling net.

While one field tech uses a shocker to stun the fish, the other captures them in her sampling net.

Waders: We use hip high and chest high waders to keep us dry as we collect fish in the stream. More importantly, they insulate us from the electric pulses discharged from the shockers, as well as the cold water temperatures, enabling us to work for long periods of time in relative comfort.

A field crew in waders samples with electroshockers, catch nets, and buckets.

A field crew in waders samples with electroshockers, catch nets, and buckets.

Hydro Lab: Another vital piece of equipment is this hand held device which measures water chemistry.  Once submerged, it gives water temperature, pH, dissolved oxygen and water conductivity readings.

The Hydro Lab is used for water chemistry analysis.

The Hydro Lab has several probes on the tip which when submerged gathers water chemistry readings.

Having the right equipment cleaned, calibrated, and working properly allows the Department of Environmental Protection staff to accurately record and assess the quality of our streams and watersheds.  As you can tell, instrument care and maintenance is an integral part of our monitoring program.

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Magical Fairy Shrimp

Posted by mocobio on June 30, 2009

Although most shrimp are found in oceans, fairy shrimp live in fresh or saltwater ponds. They are invertebrates, meaning they lack a backbone. Fairy shrimp are known as an indicator species because they are highly sensitive to changes in their environment. Since they are sensitive to environmental conditions, they are often used by biologists and ecologists to evaluate overall environmental health. If they are present and are found thriving, it can suggest a healthy environment supportive of their life-cycle needs for habitat, food, and reproduction.

Fairy shrimp live in small temporary water holes known as vernal pools, found in locations such as wooded areas, floodplains of streams and rivers, flooded meadows, coastal regions, wetlands, and swamps. These pools are also habitat to frogs, toads, salamanders, and crayfish. By definition, if a pool supports fairy shrimp, it is a vernal pool. Any changes in hydrology such as changes in groundwater, as well as quality and flow directions of surface water can negatively impact vernal pools. One of the biggest threats to vernal pools is the paving over of natural lands by pavement and concrete which prevents rainfall from percolating into the ground and changes the water balance in an area.

Look closely... like real fairies, they are hard to find! Fairy shrimp are obligate seasonal pool invertebrates... meaning they are only able to exist in these special seasonal pool habitats.

Look closely... like real fairies, they are hard to find! Fairy shrimp are invertebrates which only live in seasonal pools. Read our post 'Vernal Pools' to learn more.

 

Fairy shrimp spend their entire lives in these pools and have a fascinating life cycle.  The female drops her eggs to the bottom of the vernal pool, which in the mid-Atlantic region of Montgomery County MD, often dry by late summer.  The eggs go into a state of diapause in which they lie dormant through freezing and drying cycles.  The eggs can hatch years later, when conditions are favorable.  The sudden appearance of fairy shrimp, from seemingly nowhere, is how they acquired their name.

Close up of elusive fairy shrimp, whose eggs lie dormant for years.  When they hatch under favorable conditions, they seem to appear out of nowhere.

Close up of fairy shrimp, whose eggs can lie dormant for years. When they hatch under favorable conditions, they seem to appear out of nowhere, hence their name.

Fairy shrimp are fun to watch swim because of their eleven sets of appendages known as phyllopods.  Phyllopods are used in collecting food and locomotion.  Fairy shrimp swim on their backs fanning their phylopods. 

Watch a video of moving fairy shrimp that a County biologist caught on video were found west of Rockville near Seneca Creek State Park at McKee Beshers Wildlife Management Area.  Aren’t they magical?

 

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Posted in Pools | 2 Comments »

Bends and Banks: Sensitive Species in a Restored Stream Site

Posted by mocobio on April 29, 2009

The Stream Valley Drive subwatershed lies within the Rock Creek Watershed. In the Stream Valley Drive tributary, historic agricultural practices, a power line crossing, and road crossings had increased stormwater flow damage in the stream such as bank erosion, and increased sediment problems. It had also incised the stream’s channel-bottom, and degraded instream habitat for fish and other creatures.

Today we went back to the Stream Valley Drive stream to evaluate how successful its 2004 restoration project has been in bringing back biological life. In 2004, DEP completed restoration on 2,380 feet of the stream at a cost of approximately $250,000. The restoration project’s goals were to:

    Protect stream quality of an important headwater tributary to Rock Creek

    Stabilize eroding stream banks

    Enhance a riparian buffer

    Improve fish passage

    Enhance floodplain access

    Establish vernal pools

    Improve instream aquatic habitat conditions and

    Restablish a stable historical channel

The large boulders (rip rap) are used to stabilize the bank and prevent additional erosion.

The large boulders (rip rap) are used to stabilize the bank and prevent additional erosion.

Rock installed at the toe of the stream bank slope stabilized the stream channel where it has erosive stresses from fast-flowing water. The slopes above the reinforced toes were graded back to create new floodplain terraces. During high flows the water could loose its erosive energy by spreading out over these floodplain terraces. The restoration project returned the stream to its original, gently meandering path, and installed rock weirs which created pools for additional wetland habitat.

Cross Vanes (lines of stone or logs which are carefully laid down at an angle) were incorporated into the restoration sections, to help turn the flow of water toward the center of the stream.  These vanes channel fast-flowing water away from the banks which prevents erosion and maintains stream bed elevation. 

Meghan looking at a log cross vane, it helps to direct flow away from banks and towards pools.  These pools are critical fish habitat.

Meghan looking at a log cross vane, it helps to direct flow away from banks and towards pools. These pools are critical fish habitat.

A good part of our post-restoration monitoring focused on the stream station. While assessing habitat, we saw some evidence that the stream restoration was working well – the stream appeared to have more natural bends and flow and the banks appeared stable in areas were rip rap was placed.

Biologists examining whether the rock cross vane functions adequately.

Biologists examining whether the rock cross vane functions adequately.

Just as we did at the created wetland, we looked at the biological indicators to tell us the full story on the success of the restoration project. We observed some benthic macroinvertebrates (aquatic insects, worms, crustaceans, and mollusks) as well as salamander reproduction which were particularly encouraging. We observed both larval northern two-lined salamanders and northern two-lined salamander egg masses when we collected our benthic macroinvertebrate sample.

ursv201_salamandereggs_061

Stream salamander eggs attached to the bottom of a rock that was sampled during benthic macroinvertebrate collection. The presence of eggs and larvae tell us that the water quality is good enough to allow for successful reproduction in this restored stream.

 The benthic macroinvertebrate sample will be processed back at the lab and compared to the pre-restoration sample and other post-restoration samples to examine how the community has changed over the life of the restoration project.

ursv201_perlidae

Stonefly larvae in the family Perlidae. Stoneflies are one of the most pollution-sensitive benthic macroinvertebrate groups. This stonefly's presence indicates that the water quality is good.

Overall, we had another great day out in the field, seeing indications of some level of success at this restoration site, collaborating with colleagues, and enjoying the sights and sounds of springtime. 

 

Spring Beauty: One of the wildflowers we encountered at the restoration site.

Spring Beauty: One of the wildflowers we encountered at the restoration site.

To learn more about the Stream Valley Drive Restoration Project, please see the Stream Valley Restoration Fact Sheet.

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Life is Thriving at a Restored Stream Site

Posted by mocobio on April 16, 2009

Restoration monitoring  is one of our main jobs as County aquatic biologists.  Following stream restoration, where the shape, channel, and habitat of a stream has been historically damaged (usually by destructively fast-flowing stormwater in urban areas), we monitor the site to assess whether the restoration efforts have been effective in reaching their stated goals (which can include: whether biological life is thriving again, and whether stream life is recovering).

The project we visited today is in the Rock Creek watershed.  As part of the restoration, wetlands were artificially constructed into the stream’s floodplains.  This is critical habitat for frogs, salamanders, and toads, particularly in their reproduction phase.

A man-made wetland pool at a stream restoration site in Gaithersburg

A man-made wetland pool at a stream restoration site in Gaithersburg

 Although stream conditions in the Upper Rock Creek watershed tend to be good to excellent, the Stream Valley Drive tributary was suffering from development impacts resulting from historic agricultural practices, a power line crossing, and road crossings. These impacts caused the stream to experience increased stormwater flows, erosion, high sedimentation, incised channels, and degraded stream habitat. Important forest and floodplain habitat was also lost.

We visited the site to evaluate one of the man-made wetland pools, assess stream habitat, and collect a benthic macroinvertebrate sample to use as an indicator of water quality.  This is the last time this site will be monitored and it marks the fifth year following restoration activities. 

Environmental scientists gathering data from the edge of the restored, created wetland.

Environmental scientists gathering data from the edge of the restored, created wetland.

The man-made wetland pool we were monitoring was alive with activity! Before arriving at the pool, we could hear the calls of northern spring peepers! We also heard several calling birds: downy, red-bellied, and pileated woodpeckers, Carolina wren, and tufted titmouse, among others. We even caught a glimpse of the red-bellied and pileated woodpeckers actively in search of food amongst the treetops.

Once at the pool, we began collecting data on the conditions of the pool and the animals and plants associated with it. The first thing noticed were over a thousand tadpoles throughout the pool – and we were thrilled!

Underwater shot of the tadpoles in the man-made wetland pool captured by Jenny.  How neat is it to see the tadpoles schooling like fish for protection?

Underwater shot of the tadpoles in the man-made wetland pool captured by Jenny. How neat is it to see the tadpoles schooling like fish for protection?

We captured a few of the tadpoles to confirm what species were present in the pool. The representatives we caught were all toad tadpoles. 

A closer view of one of many tadpoles observed at the restoration site.  Although tiny, we could tell it was a toad tadpole based on the body, coloration, and tail shape.

A closer view of one of many tadpoles observed at the restoration site. Although tiny, we could tell it was a toad tadpole based on the body, coloration, and tail shape.

 While examining the wetland pool we also found several spotted salamander egg masses! It is a great sign to see that this pool is being utilized by this very sensitive species. Spotted salamanders require seasonal pools for successful breeding, and the pools must have good water quality and remain wet long enough for the larvae to develop. Additionally, the adults retreat to upland forested habitat following breeding so this component must be present as well. Spotted salamander egg masses have been observed every year of monitoring following construction of the wetland pool, telling us that installation of this particular pool was successful. We did not take any pictures of the egg masses at this site because they were too far from the water’s edge to capture a clear photograph. We wanted to minimize disturbance to the pool so we did not enter it.

As we continued to examine the pool, we got on our hands and knees and peered closer into the pool and found many invertebrates that told us the pool is doing well – copepods, predaceous diving beetles, and water striders. These invertebrates were too quick and small to get a picture of this time!

 In addition to examining the pool itself, we looked at the area surrounding the pool. The majority of the trees and other vegetation appeared to be fairing well.

A tree planted as part of the restoration at the Stream Valley Drive Project.  The tube at its base stabilizes it and protects it from hungry deer and other wildlife

A tree planted as part of the restoration at the Stream Valley Drive Project. The tube at its base stabilizes it and protects it from hungry deer and other wildlife

 As part of our assessment, we also searched for adult amphibians and reptiles around the pool’s edge by looking under cover objects such as logs and rocks. In doing so, we found another treat – a young northern brownsnake!

The northern brownsnake we caught was just as interested in observing us as we were in it.  Its tongue was constantly flicking to pick up smells and gather information while Rachel snapped pictures.

The northern brownsnake we caught was just as interested in observing us as we were in it. Its tongue was constantly flicking to pick up smells and gather information while Rachel snapped pictures.

 Northern brownsnakes are a fairly common species of snake that feed primarily on earthworms. This species is very docile and does not bite when captured. They also very rarely musk (release a foul smell from their cloaca), so they are great ambassadors to folks who may be leery of snakes. Although relatively common, we do not encounter them very frequently and were excited to see another animal contributing to the biodiversity of the site and using the restored habitat.

Rachel examining her catch -- a young brownsnake

Rachel examining her catch -- a young brownsnake

 

Jennifer St. John with a brown snake

Jennifer St. John with a brown snake

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Posted in Amphibians and Reptiles, Pools, Stream restoration | 6 Comments »

Vernal Pools

Posted by mocobio on April 1, 2009

Here’s what a seasonal pool looks like.  They’re often just depressions and natural wet spots that fill with water in the wet spring, in forested areas.  They’re all over the landscape, near streams, in forests.  The majority of amphibians and reptiles live in and around streams, or in these seasonal pools.  These seasonal pools often dry up in the heat of the summer.  But in the springtime, they are a key wildlife habitat, and provide critical breeding grounds for our amphibians and reptiles.

seasonal wetland pool in early spring

seasonal wetland pool in early spring

We’re finding a number of calling frogs such as wood frogs, northern spring peepers, pickerel frogs and toads, as well as spotted salamanders, out this time of year. We’re noting their numbers, and looking for any anomalies on their bodies.

  The presence of adult frogs and salamanders doesn’t offer a complete assessment. We’re also searching pools for signs of successful breeding, such as egg masses or larvae, to make sure these species are surviving. Some spotted salamanders often return to the same pool annually for several years to breed…and they can live over 20 years.

Looking for tadpoles in a vernal pool
Looking for tadpoles in a vernal pool 

These pools are critical in the stream network. Pools are also a key wildlife habitat, and they are critical for breeding success. 

When monitoring frogs and salamanders, County biologists follow strict protocols to sanitize boots and equipment to minimize the risk of introducing diseases, pathogens and invasive species into the seasonal wetland pools.   

Tadpole Detail in a vernal pool

Tadpole Detail in a vernal pool

 These tadpoles have hatched from the egg masses within the past week. 

Interested in looking for vernal pools and their frogs and salamanders?  Please help maintain the ecological balance of pools by staying out of the pools and their surrounding moisture zones.  Interested residents can check with the County’s nature centers about guided walks and educational materials on seasonal pools and their wildlife.  Visit: ww.mcparkandplanning.org/Parks.

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Posted in Pools, Watershed | 2 Comments »

Canaries of Our Streams

Posted by mocobio on March 24, 2009

We biologists are busy this spring collecting data on the presence and range of amphibians and reptiles (known as herpetofauna) during the brief time when the species are actively breeding.

This herpetofauna component of the biological monitoring program provides useful information on headwater streams, where monitoring fish is not as reliable an indicator of water quality.  Monitoring a variety of species improves the County’s ability to assess biodiversity and watershed health trends.

Monitoring frogs and salamanders in seasonal pools  is an important part of DEP’s efforts to assess the health of the county’s watersheds and ecosystems. These creatures are very sensitive to stressors that impact water quality or habitat conditions. A decline in their health can be an early indicator of ecosystem problems.

 

Jenny with spotted salamanders
Jenny with spotted salamanders

 

We investigated the McKee Beshers Wildlife Management Area in the evening hours, when the salamanders and frogs come alive, and start moving around. We’re finding a number of calling frogs such as wood frogs, northern spring peepers, pickerel frogs and toads, as well as spotted salamanders. We’re noting their numbers and looking for any anomalies on their bodies.

Locate McKee Beshers Wildlife Management Area on this Map
 

Spotted salamanders getting cosy on Rachel's lap

Spotted salamanders getting cosy on Rachel's lap

 

Frogs, toads, and salamanders are all amphibians. This group of animals act like “canaries in a coalmine” for indicating water quality problems or environmental problems. All amphibians absorb water through their skin, allowing a direct route for toxins and pollutants into their bodies. These animals also rely on good water quality earlier in their lives. Their eggs must be laid out in very moist soil or directly in water. Most tadpoles and salamander larvae finish their development directly in the water. These animals are also very long-lived, most exceeding at least five years of age, and some salamanders living to over 20 years.

 

Rachel Gauza holding up a Spring Peeper

Rachel Gauza holding up a Spring Peeper

In general, we see areas of the County that are more rural and forested having a lot of amphibians and reptiles, including the sensitive and specialized ones. Areas of the County that are highly-urban (such as those closer to the District of Columbia) have much lower numbers and the specialized and sensitive species are no longer there.

 

Spotted Salamanders laid against a leaf
Spotted Salamanders laid against a leaf

During our surveys we will visiting stream sites, wetlands, and seasonal pools and search for amphibians and reptiles. We listen for calling frogs, look directly in the water for animals, and look under rocks, logs, and other places where these animals would be hiding.

 

Northern Spring Peeper on a Tree

Northern Spring Peeper on a Tree

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Posted in Amphibians and Reptiles | 1 Comment »

Watershed Conditions Mapped Out

Posted by mocobio on March 20, 2009

watershed conditions in Montgomery County

watershed conditions in Montgomery County

Biological monitoring provides a long-term, stable picture of the health of our county’s streams and watersheds, as opposed to measurements of stream water chemistry that only provide an instantaneous snapshot of conditions.  The County’s monitoring program generates data which helps to rate the biological condition of watersheds into categories of ‘excellent,’ ‘good,’ ‘fair’ or ‘poor’ condition.  See our map of watershed conditions around the County.  Also, visit our Web page: www.montgomerycountymd.gov/DEP for more information.

Posted in Watershed | 2 Comments »