26 de mayo de 2020

Calvert County Damselflies & Dragonflies: Part 19 – Forktail/Sprite Damselflies of the Family Coenagrionidae Family: Coenagrionidae (Forktails/Sprites)

Family: Coenagrionidae (Forktails/Sprites)

This is the third and final family of damselflies to be examined in this series of posts. Due to the large number of species present for the Coenagrionidae damselfly family, I have been breaking down this particular family into smaller segments. This is the final grouping within this family and this will also conclude the review of the various Odonata families found in Calvert County and the surrounding counties of Charles and St. Marys.

In Richard Orr’s Maryland database, there are five species of Forktail damselfly species listed as present in at least one of the three southern Maryland counties and two species of Sprites. Four of the seven species are present in all three counties. Six of the seven species have been reported in Charles County with four and five species reported for St. Marys and Calvert Counties, respectively. One of the Forktail species is on the S3 Watch List and both of the Sprite species are on the S1 or S2 list.

Unlike the the iNaturalist observation database for most damselflies in the southern Maryland counties that is very sparse, the number of observations for this group is significantly greater (as of May, 2020). This has been in large part skewed by my own abundant observations of Rambur’s Forktails. Currently there are not any observations for two of the Forktail species and none for the two Sprite species. St. Marys County has a total of four observations for two species (Rambur’s x 3, Fragile x 1), and Charles County also has four observations but for a single species (Eastern). Calvert County is discussed below.

During the summer of 2019, I developed a fascination for Rambur’s Forktails. They were the first species of damselfly that I had ever bothered to examine closely. This was due in large part because they could easily be observed in my own yard. A portion of my yard is in contact with a brackish body of water (Lake Charming) and once I discovered the existence of this particular species, I could observe them on a daily basis. I was rewarded with my first views of damselfly mating behavior, but also confronted with the challenge of trying to photograph such a small insect. Of the 25 Calvert County Rambur’s Forktails observations in the iNaturalist database, 21 are mine. My observations in 2019 started on 24 June and they were last observed in mid-October. In 2020 my first observation of a Rambur’s Forktail in the yard area was on May 8th, the day before a frost warning struck the area. The identification has not been confirmed (i.e., not research grade). No other individuals were sighted until yesterday (May 25th). A male and a female were observed, but I was only able to capture the female photographically. The second forktail damselfly recorded for Calvert County is the Fragile Forktail. Four of the seven observations were recorded recently (spring, 2020) including two from me.

Listed below are the species within this group that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of May, 2020). As was done with the previous family, I have included notes extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the four species that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Citrine Forktail/Ischnura hastata
In the Azores, researchers discovered a population of Citrine Forktails that were able to produce fertile eggs in the absence of males. This is the only documented case of parthenogenesis in damselflies or dragonflies. (1)
Cove Point adult abundance and flight period – uncommon/21-Apr to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present ​Charles - present

Lilypad Forktail/Ischnura kellicotti
S3 Watch List (see below for definition)
Many species of damselflies and dragonflies exhibit sexual dimorphism (male and female look different). In the case of Lilypad Forktails, the females also exhibit polychromism and can be found in three different color forms. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X Charles - present

Fragile Forktail/Ischnura posita
Fragile Forktails are our most common and widespread damselfly. They have a wide habitat tolerance and can be found at nearly every pond, marsh, or slow-moving stream. (1)
Cove Point adult abundance and flight period – abundant/01-Apr to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 7 (Mar-May) St. Marys = 1 (Jul) Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Rambur’s Forktail/Ischnura ramburii
Damselflies identification is often based on the species-specific shape of the appendages at the tip of the abdomen which the male uses to grasp the female during mating. (1)
Cove Point adult abundance and flight period – abundant/21-Apr to 14-Oct. (2)
iNaturalist research grade observations:​ Calvert = 24 (May-Oct) St. Marys = 3 (Jun-Sept) Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Eastern Forktail/Ischnura verticalis
Female Eastern Forktails mate only once and carry up to 2,000 eggs. (1)
Cove Point adult abundance and flight period – common/21-Apr to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 4 (Apr-Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles – present

Sphagnum Sprite/Nehalennia gracilis
S2 Watch List (see below for definition)
The Sphagnum Sprite, as its name implies, lives in sphagnum-choked bogs and fens. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X Charles - present

Southern Sprite/Nehalennia integricollis
S1/S2 Watch List (see below for definition)
The Southern Sprite is one of our smallest damselflies. It is easly overlooked because it is inconspicuous and rarely flies unless disturbed. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X Charles - X

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S1 - Critically Imperiled / Highly State Rare — At very high risk of extinction or extirpation due to very restricted range, very few populations or occurrences, very steep declines, very severe threats, or other factors. Typically occurring in five or fewer populations.

S2 - Imperiled / State Rare — At high risk of extinction or extirpation due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors. Typically occurring in 6-20 populations.

S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Publicado el mayo 26, 2020 09:23 TARDE por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

08 de mayo de 2020

Calvert County Damselflies & Dragonflies: Part 18 – Bluet Damselflies of the Family Coenagrionidae

Family: Coenagrionidae (Bluets)

This is the third and final family of damselflies to be examined in this series of posts. Due to the large number of species present for the Coenagrionidae damselfly family, I have been breaking down this particular family into smaller segments. This grouping is comprised entirely of the genus Enallagma, the Bluets.

In Richard Orr’s Maryland database, there are eleven species of Bluet damselfly species listed as present in at least one of the three southern Maryland counties. Seven of those species are present in all three counties. All eleven species have been reported in Charles County with nine and seven species reported for St. Marys and Calvert Counties, respectively. Five of the eleven species are on the S3 Watch List.

The iNaturalist observation database for all damselflies in the southern Maryland counties is quite sparse and once again the same pattern continues with this group. There are only 10 research grade observations in total for the three counties and five of that total were submitted by me, all in Calvert County (Big Bluet x 4, Familiar Bluet x 1). They are the only Calvert County observations. St. Marys County has a single observation for each of two species (Big Bluet and Familiar Bluet), and Charles County has three observations total for two species (Big Bluet x 2, Orange Bluet).

Listed below are the species within this group that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of March, 2020). As was done with the previous family, I have included notes extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the six species that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Azure Bluet/Enallagma aspersum
Damselflies and dragonflies have large compound eyes that dominate the head. They also have three small, simple eyes that lie near the top and middle of the head. The extra eyes are called ocelli and are believed to provide close-up vision. (1)
Cove Point adult abundance and flight period – common/05-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present ​ Charles - present

Double-striped Bluet/Enallagma basidens
The Double-striped Bluet represents one of the most dramatic range expansions in the US. Prior to 1930, it was unknown north and east of Texas. In just over 50 years it has expanded its range to the eastern US and as far north as New York. (1)
Cove Point adult abundance and flight period – uncommon/05-Jun to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Familiar Bluet/Enallagma civile
Familiar Bluets feed away from water and hover over plants to pluck insects from leaves instead of catching them in flight. (1)
Cove Point adult abundance and flight period – abundant/04-May to 02-Dec. (2)
iNaturalist research grade observations:​ Calvert = 1 (Oct) St. Marys = 1 (Sept)​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Attenuated Bluet/Enallagma daecki
S3 Watch List (see below for definition)
In the late 1800’s, damselflies were considered as a subgroup among dragonflies rather than the separate group equal to dragonflies as currently cataloged. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present Charles - present

Turquoise Bluet/Enallagma divagans
S3 Watch List (see below for definition)
Adults can survive under water when ovipositing. Presumably the hairs on their thorax help to create a bubble of air that enables them to breathe underwater. (1)
Cove Point adult abundance and flight period – rare/16-Jun. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr): ​Calvert – present St. Marys – present Charles – present

Big Bluet/Enallagma durum
S3 Watch List (see below for definition)
The Big Bluet is known for its salt tolerance and is common in freshwater estuaries along the northeastern Atlantic Coast. (1)
iNaturalist research grade observations:​ Calvert = 4 (Jul-Aug) St. Marys = 1 (Jun) Charles = 2 (Jun-Aug))
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Stream Bluet/Enallagma exsulans
The Stream Bluet is a delicate damselfly that prefers Piedmont streams, while most of its bluet relatives prefer ponds. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X​ Charles - present

Skimmming Bluet/Enallagma geminatum
Studies of mitochondrial DNA from bluets indicate that the many species of bluets found in DelMarVa represent a recently evolving species swarm (a group of closely-related species), recently meaning the last period of glaciation. (1)
Cove Point adult abundance and flight period – rare/04-Jun. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Orange Bluet/Enallagma signatum
Damselflies are often observed flying in tandem even after mating which assures that no other male can mate with the female. (1)
Cove Point adult abundance and flight period – common/03-Sept to 14-Oct. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 1 (Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Slender Bluet/Enallagma traviatum
S3 Watch List (see below for definition)
Look for Slender Bluets in June and July in the vegetation along the shores of ponds. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present Charles - present

Vesper Bluet/Enallagma vesperum
S3 Watch List (see below for definition)
Approximately 90% of dragonfly and damselfly species found in DelMarVa had been described by 1919, the year that the Vesper Bluet was first described. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X​ Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Publicado el mayo 8, 2020 06:07 TARDE por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

03 de abril de 2020

Calvert County Damselflies & Dragonflies: Part 17 – Damsel and Dancer Damselflies of the Family Coenagrionidae

Family: Coenagrionidae (Damsels/Dancers)

This is the third and final family of damselflies to be examined in this series of posts. Due to the large number of species present for the Coenagrionidae damselfly family, I will be breaking down this particular family into smaller segments. This grouping is comprised of three genus: Argia (Dancers) and Amphiagrion & Chromagrion (Damsels).

In Richard Orr’s Maryland database, there are seven species of Damsel or Dancer damselfly species listed as present in at least one of the three southern Maryland counties. Four of those species are present in all three counties. At the start of this lengthy review of dragonflies and damselflies, I discovered that one of the species that I had observed in my yard on multiple occasions, and had been submitted and identified in iNaturalist, was not listed by Richard Orr for Calvert County in the Maryland database. While the Blue-fronted Dancer is a common damselfly and recorded in the counties north and south of Calvert County, a verified record of its presence in Calvert County was absent (and also lacking for Charles County as well). I contacted Richard Orr and he asked me to send him locality information along with photographs of the observations. After review, the Blue-fronted Dancer has now been added to the Calvert County list of observed species. Thus, my first significant contribution to the Maryland database. Richard was very encouraging to continue searching to help expand the records for the southern Maryland area.

The iNaturalist observation database for all damselflies in the southern Maryland counties is quite sparse and the pattern continues with this group. There are only 10 observations in total for the three counties. Seven of those ten are from my own Blue-fronted Dancer submissions and they are also the only Calvert County observations. St. Marys County has zero observations, and Charles County has a single observation for each of three species (Blue-fronted Dancer, Variable Dancer, Powdered Dancer).

Listed below are the species within this group that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of March, 2020). As was done with the previous family, I have included notes extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the three species that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Eastern Red Damsel/Amphiagrion saucium
Some species such as the Eastern Red Damsel have narrow habitat preferences that are rare or sites that are infrequently visited by humans such as grassy spring seepage areas that this species prefers. (1)
Cove Point adult abundance and flight period – uncommon/10-May to 14-Jun. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr): ​Calvert – present St. Marys – present ​Charles - present

Blue-fronted Dancer/Argia apicalis
A study in Oklahoma found that the average estimated adult life span of the Blue-fronted Dancer was a little over eight days. (1)
iNaturalist research grade observations:​ Calvert = 7 (Jun-Aug) St. Marys = 0 Charles = 1 (Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - X

Seepage Dancer/Argia bipunctulata
The Seepage Dancer is among the rarest damselfly on the DelMarVa Peninsula and among the most threatened because it prefers boggy, seepage habitats such as sea-level fens that are typically smaller than an acre and are rare on the DelMarVa Peninsula. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X Charles - present

Variable Dancer/Argia fumipennis
Several subspecies received the name Variable Dancer to recognize the diverse appearance of the species over its range. (1)
Cove Point adult abundance and flight period – rare/19-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 1 (Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Powdered Dancer/Argia moesta
The Powdered Dancer only occurs on Piedmont streams and typically perches on rocks in the middle of riffles and short rapids. (1)
Cove Point adult abundance and flight period – rare/24-Jul. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 1 (Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X Charles – present

Blue-tipped Dancer/Argia tibialis
The Blue-tipped Dancer prefers slow-moving, forested streams with silty bottoms and likes to perch on the barkless trunks of fallen trees, twigs, grass, and bare ground along the shore and in nearby woodlands. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Aurora Damsel/Chromagrion conditium
S3 Watch List (see below for definition)
The Order Odonata includes two major suborders, Anisoptera and Zygoptera, corresponding to dragonflies and damselflies, respectively. These names refer to the differences in the shape of the front and hind wings. Dragonflies have different wing shapes while the damselfly wings are of similar shape. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Publicado el abril 3, 2020 10:14 MAÑANA por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

31 de marzo de 2020

Calvert County Dragonfly Season is Here - 30th of March, 2020

Went for a hike in Calvert Cliffs State Park yesterday (March 30, 2020) afternoon after hearing at noontime that a Maryland-wide Stay-at-Home order would go into effect at 8:00 PM in response to the Coronavirus Pandemic. I was rewarded with the first dragonflies of 2020 - many Common Green Darners zipping about the aquatic plants and seemingly never resting. Trying to get photographs was a near impossibility (for me at least), but I was able to capture one blurry image of a Darner momentarily hovering and then a second poor image of the same Darner when it landed on vegetation for a brief second. It also just missed becoming a lunchtime meal when a frog with poor aim took a shot at it as it flew by.

The Common Green Darner is truly one of the more interesting dragonflies by virtue of its migratory behavior. Their annual migration involves two migratory and one non-migratory generations. In the spring, the first generation makes a long distance northbound migration, lays its eggs, and dies. The second generation emerges and will make the return trip southward, lay its eggs, and dies. The third generation is a resident generation at the southern locale and does not migrate. They will emerge, reproduce locally, lay eggs, and then dies. Their offspring will migrate northward the following spring to complete the cycle. Reference: Hallworth, MT, et al., Biology Letters, 14(2) 2018.

Publicado el marzo 31, 2020 07:47 TARDE por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

27 de marzo de 2020

Calvert County Damselflies & Dragonflies: Part 16 – Damselflies of the Family Lestidae

Family: Lestidae (Spreadwings)

In the Richard Orr Maryland database, there are eleven Spreadwing damselfly species listed for the state. Only five of those species are listed as present in at least one the three southern Maryland counties.

The iNaturalist observation database for the Spreadwing damselflies in the southern Maryland counties is quite sparse. Only two species are recorded from a total of only five observations: Calvert County has a single observation for a Slender Spreadwings, St. Marys County has zero observations, and Charles County has four observations in total from two species (Slender x 3, Great x 1).

Listed below are the species within this group that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of March, 2020). As was done with the previous family, I have included notes extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the four species of Spreadwing that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Great Spreadwings/Archilestes grandis
The Great Spreadwings is the largest damselfly found in the northeastern US and is a little over two inches in length. (1)
Cove Point adult abundance and flight period – rare/11-Sept to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0 Charles = 1 (May)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X ​ Charles - X

Southern (Common) Spreadwings/Lestes australis
DNA analysis seems to indicate that the Southern Spreadwings and the Common Spreadwings are subspecies of the Sweetflag Spreadwings. (1)
Cove Point adult abundance and flight period – common/23-Apr to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Elegant Spreadwings/Lestes inaequalis
The Elegant Spreadwings is one of the larger Spreadwings damselflies in our area. It prefers shallow ponds with plenty of emergent vegetation. (1)
Cove Point adult abundance and flight period – rare/16-Jun. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr): ​Calvert – present St. Marys – X Charles - present

Slender Spreadwings/Lestes rectangularis
In contrast to butterflies and moths, damselflies and dragonflies do not emerge from a pupa. Rather the larvae will climb out of the water onto a secure perch and transform into an air-breathing adult in its final molt. (1)
Cove Point adult abundance and flight period – rare/19-May to 29-Aug. (2)
iNaturalist research grade observations:​ Calvert = 1 (Jun) St. Marys = 0 Charles = 3 (Jun-Aug)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Swamp Spreadwings/Lestes vigilax
Damselfly larvae have long slender bodies with three flat paddles known as caudal gills attached to the end of the abdomen. In addition to being highly vascularized to exchange oxygen, the gills also function like a fish’s tail for mobility. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Publicado el marzo 27, 2020 01:04 TARDE por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

25 de marzo de 2020

Calvert County Damselflies & Dragonflies: Part 15 – Damselfly Introduction and the Family Calopterygidae

Damselfly Introduction:
Maryland is represented by three families of damselflies comprised of a total of 57 species:
1) Calopterygidae (Jewelwings/Rubyspots) with 7 species;
2) Lestidae (Spreadwings) with 11 species; and
3) Conagrionidae (Damsels/Dancers/Bluets/Forktails/Sprites) with 39 species.

Richard Orr’s Maryland database information on the three southern Maryland counties have a reported 31 of the 57 Maryland species with 24 of those 31 species listed in Calvert County. A Cove Point (Calvert County) report lists 18 species as being present at that location with 8 of those being common to abundant.

The iNaturalist database for damselflies in the southern Maryland counties has only 12 species reported and the following number of research grade observations/number of species within each county:
Calvert County = 68 observations/7 species, St. Marys County = 6 observations/4 species, and Charles County = 19 observations/9 species. Obviously, much work remains to be done to bring the two databases closer in alignment.

Family: Calopterygidae (Jewelwings/Rubyspots)

The Ebony Jewelwing is the only member of this family found in southern Maryland and it has been reported in all three counties according to Richard Orr’s database. It is represented in the iNaturalist database for only two of the southern Maryland counties, Calvert and Charles Counties. For this species, my contribution to the Calvert County iNaturalist database has been a pair of observations made from Battle Creek Cypress Swamp where numerous individuals were sighted throughout the park.

Listed below are the observations for the three southern Maryland counties and a comparison of the two databases is made (as of March, 2020). As was done with the dragonfly families, I have included a note extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on this species as observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Ebony Jewelwing/Calopteryx maculata
If a female has mated recently, the next male to copulate will remove the previous suitor’s spermatheca from the female and replace it with his own. (1)
Cove Point adult abundance and flight period – common/23-Apr to 29-Jul. (2)
iNaturalist research grade observations:​ Calvert = 28 (May-Aug)​ St. Marys = 0 Charles = 8 (May-Jun)
MD Biodiversity (i.e., Richard Orr):​Calvert – present St. Marys – present​Charles - present

Publicado el marzo 25, 2020 11:19 MAÑANA por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

22 de marzo de 2020

Calvert County Dragonflies and Damselflies: Part 14 – Meadowhawk & Saddlebag Dragonflies of the Family Libellulidae

Family: Libellulidae (Meadowhawks/Saddlebags)

Due to the large number of species present for this family, I have continued to break down this particular family into smaller segments. This grouping is the conclusion for the Libellulidae family and it also concludes the review of the dragonfly families found in southern Maryland. The next set of entries will be a review of the damselfly species of southern Maryland and in particular of Calvert County.

Four of the five species listed below can be found in all three southern Maryland counties according to Richard Orr’s database. The Red Saddlebags is only listed for Calvert County and is thought to probably be a stray species. While four of the five species in this grouping of dragonflies are represented in the iNaturalist database for at least one of the southern Maryland counties, the Blue-faced Meadowhawk (on the S3 Watch List) and the Black Saddlebags only have a single observation with each in Charles County.

For this group, I have made contributions for two of the species to the Calvert County iNaturalist database: 2 of the 3 observations for the Carolina Saddlebags and the first and only observation of an Autumn Meadowhawk dragonfly. These four observations in total for the two species are the only ones in Calvert County for this grouping.

Listed below are the species within this group that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of March, 2020). As was done with the previous family, I have included notes extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the four species of this group that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Blue-faced Meadowhawk/Sympetrum ambiguum
S3 Watch List (see below for definition)
This species favors vernal ponds to lay their eggs in late summer/early fall. This strategy avoids fish predators, but runs the risk of the pond drying out before the larvae hatch the following year. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0 Charles = 1 (Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Autumn Meadowhawk/Sympetrum vicinum
On the DelMarVa Peninsula there are reports of this species being present as late as December 8th and even later in New Jersey. It is not known what they do in fall evenings to stay warm. (1)
Cove Point adult abundance and flight period – abundant/14-Oct to 02-Dec. (2)
iNaturalist research grade observations:​ Calvert = 1 (Nov) St. Marys = 0 Charles = 8 (Sept-Nov)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Carolina Saddlebags/Tramea carolina
Prior to 1763 no dragonfly species from what is now the United States had been described. In that year the Swedish botanist Linnaeus described Tramea carolina, the Carolina Saddlebags, a species he never saw alive. (1)
Cove Point adult abundance and flight period – common/05-May to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 3 (Jun-Jul) St. Marys = 0​ Charles = 2 (May-Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Black Saddlebags/Tramea lacerata
Dragonflies have evolved capabilities that continue to challenge aircraft engineers such as the transition from hovering to high-speed pursuit. (1)
Cove Point adult abundance and flight period – common/19-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 1 (Oct)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Red Saddlebags/Tramea onusta
Like other saddlebag species, the Red Saddlebags wanders far from its emergence site. Although it normally occurs west of the Mississippi, strays occasionally make it to the eastern US. (1)
Cove Point adult abundance and flight period – rare/29-Jul. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X​ Charles – X

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Publicado el marzo 22, 2020 01:06 TARDE por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

18 de marzo de 2020

Calvert County Dragonflies and Damselflies: Part 13 – Dasher/Gliders/Amberwing/Whitetail Dragonflies of the Family Libellulidae

Family: Libellulidae (Dasher/Gliders/Amberwing/Whitetail)

Due to the large number of species present for this family, I am continuing to break down this family into smaller segments. This particular grouping is composed of a variety of dragonfly types and the common names sound strangely similar to a herd of Santa’s reindeers.

All five of the species listed below can be found in all three southern Maryland counties according to Richard Orr’s database. Currently only three species in this grouping are represented in the iNaturalist database for all three southern Maryland counties. The two species of Gliders are currently represented by only a single St. Marys County observation of a Wandering Glider.

For this group, I have made contributions for three species to the Calvert County iNaturalist database: 18 of 41 and 10 of 42 observations for Blue Dasher and Common Whitetail dragonflies, respectively and have added all eight observations for the Eastern Amberwing.

Listed below are the species within this group that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of March, 2020). As was done with the previous family, I have included notes extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on all five of the species of this group that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Blue Dasher/Pachydiplax longipennis
The Blue Dasher is our most abundant dragonfly all summer long. In July, probably more than half of all dragonflies present are this species. It appears to be expanding its range northward on both East and West Coasts. (1)
Cove Point adult abundance and flight period – abundant/19-May to 14-Oct. (2)
iNaturalist research grade observations:​ Calvert = 41 (May-Oct)​ St. Marys = 3 (Jul-Aug) Charles = 11 (May-Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Wandering Glider/Pantala flavescens
The Wandering Glider is the only worldwide species of dragonfly and is known from every continent except Antarctica. Ships a thousand miles at sea have encountered it. (1)
Cove Point adult abundance and flight period – common/24-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 1 (Sept) Charles = 0
MD Biodiversity (i.e., Richard Orr): ​Calvert – present St. Marys – present Charles - present

Spot-winged Glider/Pantala hymenaea
This is an opportunistic species characterized by a short life cycle and a high dispersal ability. (1)
Cove Point adult abundance and flight period – common/21-May to 22-Aug. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Eastern Amberwing/Perithemis tenera
This species exhibits sexual dimorphism which is common among dragonflies and damselflies. But it also exhibits female polymorphism, the biological significance of which is unclear. (1)
Cove Point adult abundance and flight period – abundant/19-May to 03-Sept. (2)
iNaturalist research grade observations:​ Calvert = 8 (Jun-Aug) St. Marys = 2 (Jul-Sept) Charles = 3 (Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Common Whitetail/Plathemis lydia
The Common Whitetail is a striking example of sexual dimorphism. Males have a bright white abdomen and prominent black bands across both wings. Females have a brown abdomen and several dark patches on the wings. (1)
Cove Point adult abundance and flight period – abundant/21-Apr to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 42 (Apr-Sept) St. Marys = 4 (Apr-Jul) Charles = 11 (Apr-Aug)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Publicado el marzo 18, 2020 03:25 TARDE por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

16 de marzo de 2020

Calvert County Dragonflies and Damselflies: Part Twelve – Skimmer Dragonflies of the Family Libellulidae

Family: Libellulidae (Skimmers)

Due to the large number of species present for the Family Libellulidae, I have been breaking down the family into smaller segments. This segment will focus on the Skimmer dragonflies which are all contained in a single genus Libellula.

Of the ten species listed below for southern Maryland from Richard Orr’s database, nine of the ten species can be found in all three southern Maryland counties. This includes two of the three species on the S3 Watch List of the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”. In the iNaturalist database for the three southern Maryland counties as of March, 2020, species observations are as follows: Calvert – all 10 species, Charles – 9 species, and St. Marys County only 4 species recorded.

My contributions to the Calvert County iNaturalist database are as follows: entered a total of 44 observations of skimmers which included 8 of the 10 species present, but three of the eight species recorded were the result of a single observation. And of those three species, the Golden-Winged Skimmer and the Bar-Winged Skimmer are on the S3 Watch List and warrant a closer examination to insure proper identification. The Golden-Winged Skimmer was observed near the fresh water pond at Calvert Cliffs State Park which would be consistent with its expected habitat, but it can be difficult to differentiate from the Needham’s Skimmer dragonfly.

Listed below are the Skimmer species within the Libellulidae family that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of March, 2020). As was done with the previous family, I have included with most species a note extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the four Pennant species of this family that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Golden-Winged Skimmer/Libellula auripennis
S3 Watch List (see below for definition)
This species is difficult to distinguish from the Needham’s Skimmer and it has not yet been confirmed on the DelMarVa peninsula. (1)
iNaturalist research grade observations:​ Calvert = 1 (May) St. Marys = 0 Charles = 2 (Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X Charles – present

Bar-Winged Skimmer/Libellula axilena
S3 Watch List (see below for definition)
This skimmer frequently selects perches on dead tree twigs, sometimes more than 20 feet above vernal ponds. (1).
Cove Point adult abundance and flight period – rare/14-Jun to 08-Jul. (2)
iNaturalist research grade observations:​ Calvert = 2 (May-Aug)​ St. Marys = 0​ Charles = 1 (May)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Spangled Skimmer/Libellula cyanea
Along the front edge near the tip of each wing of a dragonfly is a pigmented spot called the stigma. Because this feature is absent in many fossilized dragonfly wings, it is relatively new by geological standards and is presumed to be important. (1)
Cove Point adult abundance and flight period – common/19-May to 08-Jul. (2)
iNaturalist research grade observations:​ Calvert = 4 (Jun-Jul)​ St. Marys = 0​ Charles = 6 (Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Yellow-Sided Skimmer/Libellula flavida
S2 Rare/S3 Watchlist (see below for definition)
Some 1920’s publications suggest that this species was once common on the Western Shore of the Chesapeake Bay, but certainly that is not the case today. (1)
Cove Point adult abundance and flight period – rare/24-May to 24-Jul. (2)
iNaturalist research grade observations:​ Calvert = 1 (Jul) St. Marys = 0 Charles = 2 (Jun-Jul)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Slaty Skimmer/Libellula incesta
Dragonfly larvae breathe by constantly circulating water over rectal gills that line the inside of the abdomen and extract oxygen from the water. (1)
Cove Point adult abundance and flight period – common/04-Jun to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 12 (Jun-Aug) St. Marys = 2 (May-Jul)​ Charles = 9 (Jun-Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Widow Skimmer/Libellula luctuosa

Dragonflies that have emerged have small spiracles (holes) on the sides of their bodies where air enters a branching labyrinth of smaller and smaller tubes (tracheae). This enables oxygen to diffuse over a relatively short distance. (1)
Cove Point adult abundance and flight period – common/19-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 11 (Jun-Jul) St. Marys = 4 (Jun-Sept)​ Charles = 8 (Jun-Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles – present

Needham’s Skimmer/Libellula needhami

The species is named for James Needham, an entomology professor at Cornell University, by one of his students. It is abundant along salt marshes and rarely found at inland ponds. (1)
Cove Point adult abundance and flight period – abundant/19-May to 14-Oct. (2)
iNaturalist research grade observations:​ Calvert = 50 (Jun-Aug)​ St. Marys = 4 (Jun-Aug)​ Charles = 14 (Jun-Aug)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Twelve-Spotted Skimmer/Libellula pulchella

When a dragonfly locks onto a prey, it is able to adjust its flight so that it takes a direct line to an intercept point rather than a longer sweeping arc that would be generated by always flying directly toward the prey. (1)
Cove Point adult abundance and flight period – rare/17-Jun. (2)
iNaturalist research grade observations:​ Calvert = 1 (Jun)​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles – present

Painted Skimmer/Libellula semifasciata
At their breeding sites, most dragonflies are territorial. Males find prominent perches overlooking the territory they will defend and normally return to that same perch after each time they fly out to challenge an intruder. (1)
Cove Point adult abundance and flight period – uncommon/04-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 4 (May-Aug)​ St. Marys = 0​ Charles = 1 (Jun)
MD Biodiversity (i.e., Richard Orr): ​Calvert – present St. Marys – present​ Charles - present

Great Blue Skimmer/Libellula vibrans
In most years Great Blue Skimmers are scarce, but in wet years when woodland pools fill up with water in the spring and stay wet into the summer, Great Blue Skimmers are common. (1)
Cove Point adult abundance and flight period – uncommon/24-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 26 (May-Aug)​ St. Marys = 4 (May-Aug) Charles = 19 (May-Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S2 - Imperiled / State Rare — At high risk of extinction or extirpation due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors. Typically occurring in 6-20 populations.

S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Publicado el marzo 16, 2020 10:07 TARDE por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

03 de marzo de 2020

Calvert County Dragonflies and Damselflies: Part Eleven – Pondhawk/Dragonlets/Corporal Dragonflies of the Family Libellulidae

Family: Libellulidae (Pondhawk/Dragonlets/Corporal)

Due to the large number of species present for this family, I will continue to break down this family into smaller segments. This particular grouping is composed of a variety of dragonfly types.

Three of the four species listed below can be found in all three southern Maryland counties according to Richard Orr’s database. The S1 - Critically Imperiled / Highly State Rare Little Blue Dragonlet is only known from Calvert and Charles Counties and is currently lacking any southern Maryland iNaturalist observations. Both the Eastern Pondhawk and Blue Corporal dragonflies are represented in the iNaturalist database for each of the three southern Maryland counties. For this group, I have made a small contribution to the Calvert County iNaturalist database: seventeen of the 59 Eastern Pondhawk observations and one of the eight observations for the Seaside Dragonlet.

Listed below are the species within this group that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of February, 2020). As was done with the previous family, I have included notes extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the three species of this group that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Eastern (Common) Pondhawk/Erythemis simplicicollis
This is one of our most common and widespread dragonflies. It is a formidable predator that has a preference for larger prey including large flies, butterflies, and even other dragonflies. (1)
Cove Point adult abundance and flight period – abundant/05-May to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 59 (May-Oct)​ St. Marys = 9 (May-Sep) Charles = 11 (May-Sep)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Seaside Dragonlet/Erythrodiplax berenice
This is the only truly marine dragonfly in the world in that its larvae can live in seawater. (1)
Cove Point adult abundance and flight period – uncommon/24-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 8 (Jun-Jul) St. Marys = 3 (Jun-Aug) Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Little Blue Dragonlet /Erythrodiplax minuscula
S1 - Critically Imperiled / Highly State Rare (see below for definition)
The first documented occurrence on the DelMarVa peninsula of this Maryland rarity did not occur until July, 2009. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X Charles - present

Blue Corporal/Ladona deplanata
This dragonfly is one of the earliest dragonflies to emerge in the spring. (1)
Cove Point adult abundance and flight period – abundant/01-Apr to 21-May. (2)
iNaturalist research grade observations:​ Calvert = 2 (Apr-May) St. Marys = 1 (Apr) Charles = 5 (Apr-Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S1 - Critically Imperiled / Highly State Rare — At very high risk of extinction or extirpation due to very restricted range, very few populations or occurrences, very steep declines, very severe threats, or other factors. Typically occurring in five or fewer populations.

Publicado el marzo 3, 2020 10:23 TARDE por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario