Natural Notes: Habitat exploration in a Chesapeake Bay park

Date:  11 July 2014

Time:  10am-2pm
Location:  Flag Ponds Nature Park, Calvert County, Maryland, USA
Weather:  85 degrees F, Sunny, 10% cloud cover, calm wind

On Friday, July 11th I had the opportunity to participate in a habitat survey and exploration at Flag Ponds Nature Park, a protected natural area along the Chesapeake Bay in Calvert County, Maryland.  The park features coastal plain forest, maritime forest, swamp forest, freshwater marsh (see Figure 1), sand dunes, beach, and shallow brackish tidal marshes.  The coastal plain forest is dominated by various oaks (Quercus spp.), Tulip Trees (Liriodendron tulipifera), Black Gum (Nyssa sylvatica), and other overstory trees common to the Mid-Atlantic coastal plain.  The understory consists primarily of Spicebush (Lindera benzion), American Holly (Ilex opaca), Mountain Laurel (Kalmia latifolia), and other small trees and shrubs.  Wet lowland areas consisted of red maple (Acer rubrum), lots and lots of pawpaw (Asimina tribola), Arrow Arum (Peltandra virginica), Lizard's Tail (Saururus cernuus L.), and others.  The common plants in the sand dune areas consist of American Beach Grass (Ammophila breviligulata), Sand Burs (Cenchrus sp.), Russian Thistle (Salsola kali), Eastern Prickly Pear cactus (Opuntia humifusa), and others.  In between the upland forests and the dune and beach areas is a thin strip of maritime forest, whose composition varies greatly from its neighboring coastal plain forest with many of the dominant plants being evergreen.  The most common overstory tree in the maritime forest at Flag Ponds Nature Park is the Loblolly Pine (Pinus taeda) (see Figures 2 and 3). The park's more southerly location in Maryland combined with moderation from the warmer waters of the Chesapeake Bay allow for a mix of northern and southern flora and fauna to thrive, explaining in part the park's high biodiversity.

Figure 1:  Freshwater wetland and pond area at Flag Ponds Nature Park.  The light green layer on the water's surface is Duckweed (Lemna spp.),  a small floating aquatic plant.  The grasses creeping in from the left are Common Reed (Phragmites australis), an aggressive invasive plant that takes over wetland areas.  The green shrubs along the edge of the water are southern wax myrtles.  

Figure 2:  Loblolly pines tower over the maritime forest community along the Duncan's Pond trail at Flag Ponds Nature Park.

Figure 3:  The trunk of a Loblolly pine.

The maritime forest's understory is dominated primarily by southern wax myrtle (Morella cerifera) as well as some Virginia Pine (Pinus virginiana).  

The habitat survey/exploration revealed some interesting findings, as some of the plant communities didn't fit neatly into the description of an upload forest versus a maritime forest versus sand dunes (we did not investigate marshes and tidal areas very thoroughly, so I will not discuss those area any further in this blog post).  

The first area we explored was a section of wetland forest in the northern section of the park that had extremely dense thickets of pawpaw (perhaps as many as 10 individuals per 3 cubic feet), making this area difficult to pass through.  Occasionally we encountered a blackhaw viburnum (Viburnum prunifolium) or an American Holly.  At the margins of this pawpaw thicket is where we encountered a gradual transition into freshwater wetlands with Lizard's Tail, Arrow Arum, and other wet-loving plants.  In some of the more open and sunnier wetland and pond edges was the showy Swamp Rose (Rosa palustris), a native rose shrub that is also planted ornamental for its bright pink flower and low water and fertilizer needs (see figure 4).  

Figure 4:  The blossom of a Swamp Rose.  

Perhaps the most eye-opening moment of the habitat exploration was the stark contrast in habitat and the associated plant community that we encountered on the other side of Duncan's pond that seemed to be an odd fusion of a maritime forest and a sand dune (see Figure 5).  Growing on this flat sandy plain only a few feet away from a wetland community were dry and heat-loving plants such as Chinquapin Oak (Quercus meuhlenbergii) (see Figure 6), seaside goldenrod (Solidago sempervirens), Eastern Redceder (Juniperis virginiana), and others.

Figure 5:  A dry and sandy area in Flag Ponds in between a pond and a sand dune offered a blend of a sand dune environment and maritime forest.

Figure 6:  The leaf of the Chinquapin oak, and oak tree that thrives in warm, dry areas in the Southeast and Mid-Atlantic.  

We also saw lots of highbush blueberries (Vaccinium corymbosum) in this drier woodland area, although to our dismay it was too late in the season for there to be much ripe fruit available (we did however eat lots and lots of the invasive Wineberry, Rubus phoenicolasius, growing on disturbed areas near the parking lot).  Bird life was minimal due to the heat, however, we did encounter the distinct row pattern of holes on a Loblolly pine that a yellow-bellied sapsucker had made (see figure 7).

Figure 7:  The probe holes from a yellow-bellied sapsucker that was hunting for insects amongst the sap of a Loblolly Pine in Flag Ponds Nature Park.

Flag Ponds Nature Park is a beautiful representation of habitats along the Chesapeake Bay shoreline, with some rather unusual habitats mixed in that make this park unique!