Fruit of the Vine

 

Muscadine Grape (Vitis rotundifolia). 
Lincoln County, North Carolina. 

Vines are trailing or climbing plants with long stems.  Vines with woody stems are technically called lianas while those with herbaceous stems are just vines.  One of the world’s best-known vine (liana) is Grape (Vitis sp.).

Vineyards of Common Grapes (Vitis venifera).
Collioure, France.  

People domesticated grapes (Vitis vinifera) about 8000 years ago in the Middle East.  The versatile fruit of this vine can be eaten raw, dried into raisins and, of course, fermented into wine.  The earliest known wine production was in the mountains of Iran about 5000 years ago and the drink has been going strong ever since.

 North America has about 25 species of Vitis. The Viking, Leif Ericsson found Fox Grapes (Vitis labrusca) growing along the coast of what is now the Canadian Maritimes in about 1000 AD. This plant so impressed the Viking explorers they called the region Vinland. The Fox Grapes were so abundant, the Vikings immediately began to make wine on the newly discovered continent.  

Fox Grape vines with flowers (Vitis labrusca).
Rowan County, North Carolina. 

Fox Grape fruits.
Rowan County, North Carolina. 

Grapes are classified in the family Vitaceae and there about 8 native species in the Southeastern United States.  Grapes are borne on woody, deciduous vines.  Grapevines flower in spring, making green, wind- pollinated flowers.  These develop into bunches of juicy, dark purple berries by late summer.  These fruits are feasted upon by many mammals and birds. Grape seeds pass through the digestive tract of these animals unharmed and are deposited some distance from the parent vine to establish new plants.  

Young vines of Muscadine Grape growing on the forest floor.
Rowan County, North Carolina. 

Muscadine Grape Vine rambling.
Rowan County, North Carolina. 

Grape seeds require full sun to germinate, then the young vines grow across the ground seeking vertical support.  Grapevines scramble onto other plants and use tendrils to attach to branches. Grapes need bright sun to thrive, so they live at forest edges although some vines are found deep in the woods.  

Young Muscadine Grape tendril.
Clayton County, Georgia. 

Vitis sp. growing into the forest canopy.
Rowan County, North Carolina. 

Grapevines in mature forests do not grow to the trunk of the host trees like other vines but seem to vault directly from the ground to the canopy. How do they get into the tops of tall trees?  There are a couple of explanations for this strange observation.  One is the vine could have grown into the canopy on smaller trees that have died.  Another explanation is the grapevine might have grown onto the tree when it was a sapling and rode up into the canopy as the tree got taller. 

 

Porcelain Berry (Ampelopsis glandulosa)
is an invasive relative of grape.
Mecklenburg County, North Carolina. 

Porcelain Berry (Ampelopsis glandulosa) is an invasive member of the Vitaceae that is found throughout Eastern North America.  This native of East Asia is also a woody vine and it produces grape-like berries.  Porcelain Berry vines can have purple, blue, green and porcelain white berries all in the same cluster.  Like grapes, the Porcelain Berries are distributed by birds and other animals.  It has become a serious pest in some areas, shading out native shrubs and small trees.    

Porcelain Berry vines and fruits  growing in a tree canopy.
Guilford County, North Carolina. 
Drone photo courtesy of Dr. Joe Poston

Grapes and humans have a long history.  The vine was taken under domestication early in the agricultural revolution and has traveled around the world with people.  Grapes contribute hundreds of billions of dollars to the United States economy each year and wine is produced in every American state. Before modern sanitation, is was often safer to drink wine than water.  In addition to the protection from water-borne diseases, wine also contains alcohol, a mind-altering substance. These two important features of wine probably led to its place of importance in many world religions. Beyond the economic and cultural impacts of grapes, they are keystone species in natural ecosystems.  I will continue to explore other vines in upcoming editions of this blog. Thanks to Dr. Jay Bolin for his generous help with grape identification. 

Muscadine vine with woody tendril.
Rowan County, North Carolina. 

Life in the Saltmarsh - Part 2

 

Saltmarsh in summer.
McIntosh County, Georgia. 

Southeastern saltmarshes are like a string of emeralds strung along the coast.  They are found up coastal rivers, lining estuaries and in the lee of barrier islands. The water in saltmarshes is brackish with a mix of fresh water from rivers and seawater coming in on the tide.  Saltmarshes are highly productive ecosystems and in the southeast this productivity starts with the flowering plant Saltmarsh Cordgrass, Spartina alterniflora. Other plants, animals and microbes contribute to the stunning biodiversity of this unique habitat. 

Eastern Oysters (Crassostrea virginica) starting a saltmarsh oyster bar.
Huntington Beach State Park, South Carolina. 

A large oyster bar at low tide.
Huntington Beach State Park, South Carolina. 

Eastern Oysters (Crassostrea virginica) are bivalve mollusks that colonize the mud of the marsh and often form large bars.  Oyster bars stabilize the saltmarsh by catching sediment and slowing erosion.  Since mature Eastern Oysters are attached to the mud their food must come to them.  Eastern Oysters are filter feeders, taking in large volumes of water, straining out plankton and releasing the filtered water back into the marsh.   Eastern Oysters are eaten by many animals including people.  Ancient wisdom held that we should eat oysters only in months that have the letter R in them.  In other words, do not eat oysters in May, June, July and August.  There were a variety of good reasons to do this in previous centuries when all oysters were wild harvested and refrigeration was nonexistent.  Oysters spawn in the warm months and this gives them a bad taste.  Also, the filter-feeding oysters could accumulate toxic red tide organisms and slow transportation could deliver spoiled oysters to market.  Now, oysters are on the menu year-round with rapid refrigerated transport and farmed oysters that are sterile and do not spawn. 

American Mink (Neogale vison) hunting on a rock jetty
adjacent to a saltmarsh. 
Huntington Beach State Park, South Carolina. 

American Minks (Neogale vison) are mammals related to weasels and otters.  They inhabit much of North America including the edges of saltmarshes where they catch fish, invertebrates, rodents and birds.  American Minks make dens in burrows, among tree roots or in crevices between rocks where the females raise their young.  Domestic American Minks are still grown on farms and are skinned to make fur coats.     

Male Atlantic Marsh Fiddler Crab (Minuca pugnax). 
The crab is standing by the mouth
of his burrow and surrounded by mud balls.
Edisto Beach State Park, South Carolina. 

Atlantic Marsh Fiddler Crabs (Minuca pugnax) live in the mud of the marsh.  Females Fiddler Crabs have two small front claws, and the males have one large claw, the fiddle, and one small front claw.  Both males and females use the small claws to pick up particles of mud and eat the algae that coats the sand grains.  The crabs then roll the cleaned grains into mud balls and deposit them on the surface of the marsh.  Male Fiddler Crabs use their large claw to show off for females and fight with other males. This combat between males gave this crab its specific name pugnax, from the Latin for fight.  Pairs of Fiddler Crabs mate in burrows and the larval forms are released into the water at high tide. Larvae live a planktonic existence until they transform into the adult form of the crab.   

 

Blue Crab (Callinectes sapidus).
Isle of Palms, South Carolina.

Another crab of the saltmarsh is the Blue Crab (Callinectes sapidus). Blue crabs have the most apt of scientific names which translates from the Latin as tasty, beautiful swimmers.  They are beautiful and delicious.  Blue Crabs have a greenish brown carapace and blue claws and legs, including the rear paddle-shaped swimming legs.  Blue Crabs are caught on the Gulf and east coasts of the United States. Chesapeake Bay has traditionally been the heart of the Blue Crab fishing industry but overharvesting and pollution have reduced their numbers.  Many Blue Crabs eaten at the Inner Harbor of Baltimore are trapped in Louisiana.  

Seaside Sparrow (Ammospiza maritima).
Huntington Beach State Park, South Carolina. 

Several species of sparrows are saltmarsh specialists.  Seaside Sparrows (Ammospiza maritima) live in saltmarshes from Texas to New England.  These hefty sparrows have a large, pointed beak, a streaked breast, and a yellow spot in front of the eye.  Seaside Sparrows feed on Spartina seeds and insects they catch on the marsh grass.  

Saltmarsh Sparrow (Ammospiza caudacuta) on
a causeway next to a saltmarsh. 
Huntington Beach State Park, South Carolina. 

Saltmarsh Sparrows (Ammospiza caudacuta) also inhabit saltmarshes.  We see Saltmarsh Sparrows wintering in the southern marshes, but these birds breed in the Mid-Atlantic and northeastern coastal states.   Saltmarsh Sparrows are brown with streaks on the breast, orange on the face and gray cheeks. The population of Saltmarsh Sparrows has declined over 80% in the last 25 years.  Threats to this sparrow include habitat loss and sea level rise.   

Saltmarsh with Spartina behind the dunes.
Huntington Beach State Park, South Carolina. 

As with most good things, climate change is threatening saltmarshes and their inhabitants.  Sea level rise caused by the melting icecaps is the most imminent threat to saltmarshes.  The sea on the North Carolina coast has risen about one foot since 1950 and is now rising about an inch every two years.  Higher sea levels pour more salt water into the marshes.  Higher seal levels will inundate the marsh and higher salt concentration will kill the Spartina. Salt marshes can invade higher ground, but it is unlikely the newly formed marshes will keep up with the loss.  With every visit to a saltmarsh I am dazzled, but I also feel like it is slipping away.  

 

Life in the Saltmarsh - Part 1

 

Sunrise over the saltmarsh at low tide.
Huntington Beach State Park, South Carolina.

Sometimes our travels take us to saltmarshes along the southeast Atlantic coast.  One of our favorite locations is Huntington Beach State Park in South Carolina.  The park has extensive saltmarshes with numerous access points that allow easy exploration of this unique ecosystem.   

Smooth Cordgrass, Spartina alterniflora at high tide.
Huntington Beach State Park, South Carolina. 

Saltmarshes appear simple, just one species of plant for acres and miles.  But look a little closer and all manner of life can be found.  The plant that predominates southeastern saltmarshes is Spartina alterniflora or Smooth Cordgrass.  

This remarkable grass not only lives but thrives in a very harsh environment.  Twice a day the tide rolls in.  As seawater partially submerges the Spartina plants they experience dramatic changes in salinity and temperature.  These environmental fluctuations prevent other plants from growing in the marsh, so Spartina provides the basis for the saltmarsh food chain.  

Marsh Periwinkle (Littoraria irroata) on Spartina.
Huntington Beach State Park, South Carolina. 

One of the most abundant animals in the saltmarsh is the Marsh Periwinkle (Littoraria irrorata). This small snail grazes on algae in the marsh mud and on dead Spartina. Amazingly, these lowly creatures also practice a primitive form of agriculture.  Marsh Periwinkles make wounds on living Spartina stems that become infected with a fungus.  Snails that eat the fungus grow more rapidly and have a better survival rate than those without access to the fungus.  

Marsh Periwinkle on mud at low tide. 
Huntington Beach State Park, South Carolina. 

Marsh Periwinkles are preyed upon by many animals including the reclusive Clapper Rail (Rallus crepitans).  These shy, chicken-like birds are more often heard than seen.  Clapper Rails walk the marsh mud and between the stalks of Spartina where they catch not only Marsh Periwinkles but also crustaceans, small fish and insects. Clapper Rails are dark brown with fine barring on the sides, a turned up white tail and a strong beak.  When viewed from the rear, Clapper Rails look like they have been squeezed.  They are as thin as a rail.  This compressed body shape allows the Rails to slip between the Spartina stems and quickly disappear.   

Clapper Rail (Rallus crepitans) dashing across the mud at low tide.
Huntington Beach State Park, South Carolina. 

Clapper Rail about to disappear into the Spartina.
Huntington Beach State Park, South Carolina.  

Fish are abundant in the tidal creeks of the saltmarsh and are fed upon by many wading birds.  Great Blue Herons (Ardea herodias), Great Egrets (Ardea alba) and Snowy Egrets (Egretta thula) impale fish with their long, pointed beaks. White Ibises (Eudocimus albus) and Wood Storks (Mycteria americana) work their open bills through the shallow water and snap up any prey they encounter.

Great Egret (Ardea alba) and 
Great Blue Heron (Ardea herodias) fishing at low tide.
Huntington Beach State Park, South Carolina. 

Snowy Egret (Egretta thula).
Huntington Beach State Park, South Carolina. 

Snowy Egret with a fish.
Huntington Beach State Park, South Carolina. 

White Ibis (Eudocimus albus).
Huntington Beach State Park, South Carolina. 

Wood Stork (Mycteria americana).
Huntington Beach State Park, South Carolina. 

Wood Stork feeding.
Huntington Beach State Park, South Carolina. 

Double-crested Cormorants (Phalacrocorax auritus) dive in the tidal creeks and catch fish with their hooked beaks. These relatives of pelicans are found in large numbers along the coast, on inland lakes and rivers.

Double-crested Cormorant (Phalacrocorax auritus).
Huntington Beach State Park, South Carolina. 

Double-crested Cormorant with a fish.
Huntington Beach State Park, South Carolina. 

Ospreys (Pandion haliaetus) are large birds of prey and have a most dramatic fishing style.  They dive from heights, plunge into the water feet first and snatch swimming fish.  Ospreys then lift off from the water carrying their catch in their sharp talons. 

Osprey (Pandion haliaetus).
Huntington Beach State Park, South Carolina. 

Roseate Spoonbills (Platalea ajaja) have a unique feeding style.  These pink waders sweep their spatulate bills through the mud catching fish and invertebrates they encounter.     

Roseate Spoonbill (Platalea ajaja).
Huntington Beach State Park, South Carolina. 

Roseate Spoonbill feeding.
Huntington Beach State Park, South Carolina. 

Saltmarshes are remarkable places.  Despite their apparent simplicity they are quite diverse and are a key to the coastal ecosystems. Saltmarshes teem with life and serve as a bulwark against hurricanes. So much is going on here, this blog will continue exploring saltmarshes in the next installment. 

Saltmarsh.
Huntington Beach State Park, South Carolina. 

A Fall of Flamingos

 

Greater Flamingo (Phoenicopterus roseus).
Etang de Grussian, France

This fall, circumstances placed flamingos in our path.  Diane and I don’t usually see flamingos but between a hurricane and a long-planned trip to Europe we got to see two different species of these special birds. 

Tropical storm Idalia formed in the Western Caribbean in late August 2023.  It wandered about the northern tip of the of the Yucatan Peninsula of Mexico then entered the Gulf of Mexico.  The warm Gulf waters fueled Idalia’s intensification into a major hurricane.  Idalia came ashore in the Florida panhandle as a category 3 hurricane.  The storm crossed northern Florida where it weakened to tropical storm strength. It crossed southern Georgia and entered the Atlantic off South Carolina.  Idalia then swept past the coast of North Carolina and out into the North Atlantic. 

The track of Tropical Storm/Hurricane Idalia.
August-September 2023.
https://www.nhc.noaa.gov/archive/2023/IDALIA_graphics.php?product=5day_cone_with_line

Hurricanes are notorious not only for mass destruction and loss of life but also for bringing unusual birds to North America.  Many storms deposit sea birds far inland where they can be seen flying over large lakes.  Idalia did something more. 

There are large breeding colonies of American Flamingos (Phoenicopterus ruber) at the northern end of the Yucatan Peninsula.  These tall, long-legged wading birds have black wings, pink feathers and a large, curved beak.  They breed in the spring and the young birds join in large groups called creches. Young Flamingos are easy to tell from adults because they are gray rather than pink.  Flamingos eat crustaceans and other small creatures by filtering them through sieve-like structures in the beak.  The crustaceans that make up their diet contain red carotenoid pigments that are deposited in new feathers as they grow.  So, American Flamingos turn pink in their second year after consuming pigment containing food.  This species is normally found on islands of the West Indies, coastal areas of Mexico bordering the Gulf and the Caribbean, north coasts of Colombia and Venezuela, and the Galapagos Islands.   

Hurricane Idalia picked up some of the Yucatan American Flamingos and deposited then across the United States. Many ended up in Florida and around the Gulf Coast to Louisiana.  Other Flamingos found themselves far inland.  The storm-blown flamingos were recorded in Kansas, Missouri, Maryland, Virginia, Tennessee, Kentucky, South Carolina and North Carolina. 

American Flamingos (Phoenicopterus ruber).
Pea Island National Wildlife Refuge, North Carolina.
Photo courtesy of Karen Lebing. 

Hurricane Idalia brushed past the North Carolina coast on August 31 and on September 2 birders began reporting 11 American Flamingos at the Pea Island National Wildlife Refuge on the Outer Banks. Three of the birds were pink adults and 8 were gray immatures.  The flamingos persisted in the area and numbers increased to 17, with 4 adults and 13 immatures.  Diane and I did not get to see these unusual birds until September 18.  On that day the flamingos were out in Pamlico Sound, and we had to climb a dune to get distant views with a spotting scope.  This was the first time American Flamingos were recorded in North Carolina.

American Flamingos flying over Pamlico Sound.
Pea Island National Wildlife Refuge, North Carolina.

What will become of these vagrants American Flamingos?  Some could return to Mexico, others might be lost to predation, but some may stay.  An American Flamingo was blown to the St. Marks National Wildlife Refuge in north Florida by Hurricane Michael in 2018.  It has been living there ever since.  Some of the storm-tossed birds may take up residence and even breed.  There is a village named Flamingo at the south end of Everglades National Park in Florida.  American Flamingos were abundant in south Florida in the late 19^th century, perhaps they will be again, thanks to Hurricane Adalia.   

We traveled to the south of France in early October 2023 to visit friends and to see birds.  One of our targets was the Greater Flamingo (Phoenicopterus roseus). The Greater Flamingo lives in India, the Middle East, Africa and much of Mediterranean coast of Europe.  It is the largest of the world’s six flamingo species with some standing 6 feet in height.  Adult Greater Flamingos are pale pink in color with red and black on the wings that can be seen when the birds fly. Like in the American Flamingo, the first-year birds are gray and develop their color as the molt in new feathers in their second year. 

Greater Flamingos (Phoenicopterus roseus)with
the ruins of Chateau Grussian in the background.
Etang Grussian, France. 

Diane, two friends and I found a flock of dozens of Greater Flamingos in a brackish lagoon called Etang de Grussian near the Mediterranean coast of France.  The ruins of Chateau Grussian frown down on the lagoon where the flamingos fed, rested and flew about.  Other ponds in the area gave us views of hundreds more of these stunning birds.  

Greater Flamingos landing.
Etang Grussian, France. 

We rarely see wild flamingos, so for us to see two species, on two continents, in one season was a rare treat indeed.  

Greater Flamingos feeding.
Port Grussian, France.

Thanks to Karen Lebing for allowing the use of her excellent photo of American Flamingos. 

Tent Caterpillars and Webworms

 

Eastern Tent Caterpillars (Malacosoma americanum)
and web on Black Cherry (Prunus serotina). 
Rowan County, North Carolina.

There are about 12,000 species of moths in North America, and each one comes from caterpillars.  In some species this larval stage is tiny and inconspicuous, others are large and impressive.  While all caterpillars can make silk, a select group weaves a large web to house and protect the larvae.   

Two caterpillars in our area make impressive webs on trees, the Eastern Tent Caterpillar (Malacosoma americanum) and the Fall Webworm (Hyphantria cunea).

A large group of Eastern Tent Caterpillars swarming on
their web.  This tent was made in an ornamental cherry tree (Prunus sp.).
Rowan County, North Carolina. 

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Eastern Tent Caterpillars hatch in spring and build large, tent-like webs at the forks of tree branches. The caterpillars are usually found on trees in the Rose family, the Rosaceae.  We see their webs most often on Wild Cherry (Prunus serotina).  Each web may host several hundred caterpillars.  Eastern Tent Caterpillars go through 6 larval stages called instars. Each instar is larger than the last and the caterpillar molts between these stages.

A sixth instar Eastern Tent Caterpillar feeding on
Black Cherry leaves.
Rowan County, North Carolina. 

The Eastern Tent Caterpillars shelter in the web and crawl out the tree branch to feed on leaves.  The caterpillars eat several times a day and then return to the web. The web controls the temperature and humidity to give the best environment for caterpillar development.   The final instar is about two inches long, dark brown with a white stripe down the middle of the back and blue, black and yellow markings on the side.  Caterpillars of all stages have hairs called setae that help in thermoregulation and may deter predators. Birds are the main predators of Eastern Tent Caterpillars.  The birds prefer the early instars, probably because of the large, irritating setae of later stages.  The final larval stage may wander from the host tree and pupate in a sheltered location.  The moth stage of the Eastern Tent Caterpillar emerges in early spring, lays eggs on a tree and the cycle begins again. 

A sixth instar Tent Caterpillar wandering from the web.  
This one was on a metal fence post. 
Rowan County, North Carolina. 

As their name suggests, Fall Webworms appear in late summer and are present through the fall.  The Fall Webworm Moth lays eggs on the host tree in summer and when the caterpillars hatch, they immediately begin spinning their webs. The webs enclose whole tree branches, including leaves.  The caterpillars eat the soft tissue of the leaves, leaving behind the veins.  Fall Webworms remain within their web to feed and as leaves are consumed, they expand the web to include fresh leaves. Fall Webworms go through 5 larval instars in their development with the final instar being about 1½ inches long, yellow in color with long white setae. 

Fall Webworms (Hyphantria cunea) in their web. 
The host tree of this web was
an Eastern Redbud (Cercis canadensis).
Rowan County, North Carolina. 

Detail of Fall Webworms and web.
Rowan County, North Carolina.

A fifth instar Fall Webworm surrounded by
 earlier larval stages. 
Rowan County, North Carolina. 

Fall Webworms use dozens of deciduous tree species as their host. This fall in our yard they took over branches of Eastern Redbud (Cercis canadensis) and Red Mulberry (Morus rubra).  Birds are major predators of Fall Webworms. Yellow-billed Cuckoos (Coccyzus americanus) on fall migration will tear open the webs and eat dozens of the caterpillars. Fall Webworms are native to North America but have been introduced to Europe and Asia where they are considered invasive species. 

A Yellow-billed Cuckoo (Coccyzus amerianus)
eating fall Webworms.
Orange County, North Carolina. 

 

A fifth instar Fall Webworm outside the web on
Red Mulberry (Morus rubra).
Rowan County, North Carolina. 

While Eastern Tent Caterpillars and the Fall Webworms are superficially similar, they are easy to tell apart.  Eastern Tent Caterpillars appear in early spring and make their webs at the fork of tree branches.  Fall Webworms show up later in the year with webs that enclose branches including leaves.  Both these caterpillars do some damage to trees but do not kill them.  I think these two caterpillars are bookends of the growing seasons of the year.  Eastern Tent Caterpillars to open the spring and Fall Webworms to close out the warm months.  

Video of Eastern Tent Caterpillars 

and Fall Webworms.

Rowan County, North Carolina