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Ian Stewart

Jewelweed is a colorful native annual wildflower that is common in damp marshy areas where it grows as a thin bush about 4 feet high. It is also known as ‘touch-me-not’ because of its curious habit of expelling its projectile seeds when the flowers are handled or brushed against. Jewelweed is a classic folk remedy because the juice of its leaves and stems is a well-known antidote to stings and rashes from stinging nettle, which it often grows close to.

Jewelweed growing along the boardwalk at Ashland

Many Delawareans are familiar with jewelweed as it is often found in shaded suburban gardens and parks, but few people realize that there are two species and they usually grow right next to each other! The most common is spotted jewelweed (Impatiens capensis), which is also known as orange jewelweed. This has bright orange petals densely covered with red spots and a long ‘nectar spur’ which curls along the bottom of the flower. The second, less-common species is yellow jewelweed (Impatiens pallida), which is also known as pale jewelweed. This has larger, yellow flowers with only a smattering of red spots and a shorter nectar spur which dangles downward. The leaves of yellow jewelweed have more veins and are more deeply toothed than those of the orange jewelweed. In my experience, spotted jewelweed outnumbers yellow by about 5 to 1.

Side by side views of spotted (left) and yellow (right) jewelweed showing the differences in petal pattern, the length and angle of the nectar spur, and leaf venation

Jewelweed is pollinated by both hummingbirds and bees and watching these insects crawl into the depths of the flower to access the nectar pooled up in the spur is a fun way to spend a sunny afternoon! If you’re very lucky you may get to see a hummingbird feeding from the nectar spur.

A bee burrows into a jewelweed flower in search of nectar

The bee’s back is now coated in pollen from the pollen stalk dangling above it. The bee may now pollinate the next jewelweed it enters!

Both jewelweeds have a long blooming season from late spring through the early fall and are an attractive native wildflower to plant in a damp, shaded corner of your yard to attract pollinator insects and hummingbirds.

Learn more about how you can garden for native plants and wildlife by certifying your yard as a wildlife habitat through the Delaware Nature Society

https://www.delawarenaturesociety.org/what-we-do/protecting-habitats-wildlife/garden-for-wildlife/

 

Ian Stewart

Migration is a fascinating aspect of animal biology. Each spring and fall, millions of birds, mammals and insects fly thousands of miles to get to either their breeding or wintering grounds. Migration can be challenging to follow however, as many of these animals migrate at night and travel quickly. There are several methods scientists use to track migration but a new collaborative method has recently emerged: the Motus system.

The Bucktoe Motus tower

The Motus system is an international network of automated towers which detect any animal fitted with a special small tag within a 15km range (‘Motus’ = Latin for ‘movement’). Since each tag emits a unique signal it is possible to track the movement of individual animals as they pass by one of more towers. The great majority of animals fitted with tags are birds but tags have also been placed on bats and large insects like dragonflies or even butterflies! The Motus network allows scientists to collect data on tagged animals to help them find out how variables like weather and the animal’s age, sex, and physical condition affect the timing and speed of their movements. It also aids conservation efforts by identifying key areas where animals stop to feed and rest during migration which can then be protected.

There are over 200 towers spread across the world, most of which are in North America (see the map on the Motus homepage www.motus.org). In the summer of 2017 a team of dedicated field biologists erected a line of towers all the way across Pennsylvania. The towers are so close together that their detection ranges overlap, meaning that they would pick up every tagged animal that migrates north or south anywhere in the entire state!

Distribution of Motus towers across PA and DE

Thanks to generous funding from the Starrett Foundation and the Pennsylvania Department of Conservation and Natural Resources via the Willistown Conservation Trust, a Motus tower was erected at Bucktoe Creek Preserve near Kennett Square in August 2017 as part of this line and has been recording 24/7 ever since! In the fall of 2017 it detected 7 thrushes, 3 warblers, a woodcock and a bat, all presumably heading south for the winter. In the spring of 2018 it detected a thrush and 4 shorebirds, all likely heading north to breed.

Another remarkable feature of the Motus system is that much of the data is open-access and can be viewed by anyone with the Internet. To see what animals are being detected follow these 4 simple steps.

1. Visit the homepage at www.motus.org then scroll down to see a map of the world with a yellow dot representing each tower.

2. Zoom in to find the tower you’re interested in (e.g. Bucktoe Creek) and click the dot. A box will then open telling you the name of the tower and its location plus the contact details of the organization overseeing it. The bottom row gives the number of tags detected by that tower (if there have been any) with ‘table/timeline’ in parentheses next to it.

3. Click on ‘table’ and a new page will open with several columns including the date each tag was detected plus the ID# of that tag (in blue text) and the species it was placed on.

4. Click on the ID# to reveal the date and place where the animal was tagged, and then if you want to explore further, either click on ‘table’ in the bottom row to see a list of towers at which that bird was detected, or ‘timeline’ to see what time the animal passed by the tower and how long it stayed. My own favorite is to click on ‘map’ to show the route the animal took!

Every year more Motus towers are erected throughout North America and they are also starting to spread across other continents. The number of tagged animals is also steadily increasing and every time one is detected it adds to our understanding of animal migration. Watch this space for updates from the Bucktoe tower!

By Ian Stewart

The buzz around this year’s Native Plant Sale is building to fever pitch! Our plant sale comes at the perfect time as we have finally emerged from the frigid gloom of an unusually long cold winter to find colorful wildflowers emerging all across the state. These ‘spring ephemerals’ are so-named because they only flower for a fairly short time since they start losing the sunlight once the trees leaf out.

We are fortunate to have a lot of fairly common attractive native plants in Delaware, and sometimes these get taken for granted. This is a pity, as several have some surprises in store if you look at them closely. Trout Lilies are a perennial often found growing in clumps which get their name because their mottled leaves resemble the sides of a Brook Trout, a freshwater fish. However, they take between 4 and 7 years to mature so the great majority of the lilies you see don’t produce a flower and have just a single leaf (top photo). Only the older, flowering plants have two leaves (second top). The beautiful nodding Lily flowers are harder to find but tend to occur in small colonies which are often visited by insects (bottom photos).

The familiar Mayapple has a similar subtlety. This distinctive umbrella-shaped wildflower of shady forest floors is often found in dense clusters of what look like identical plants, but if you look closely you will see that some have a forked, Y-shaped stem whereas most have just a single stem (below). Only the Y-shaped stems produce a flower then later the apple-like fruit. Mayapples are actually misnamed, as in May they still only have the white flower, which is found in the base of the fork. The hanging ‘apple’ doesn’t appear until later in the summer, and despite the name, is not pleasant to eat and may even be poisonous so we do not recommend that you try it.

Delaware is blessed with a kaleidoscope of beautiful native wildflowers in our area and below are a few of my favorites (from top, Virginia Bluebell, Cardinal Flower, Great Lobelia, Butterfly Weed).

These beautiful wildflowers are available at a reasonable price at the Native Plant Sale so if you want to able to observe these natural wonders in your own back yard just come on by. As well as their visual appeal they are popular with beneficial pollinator insects like bees and butterflies, so now you can have an idyllic native garden and help nature at the same time!

The Plant Sale is held at Coverdale Farm Preserve (543 Way Rd, Greenville, Delaware) Thursday May 3rdand Friday May 4th from 3pm to 7pm (member days) and Saturday May 5th (10am – 4pm) and Sunday May 6th (11am – 3pm) (open to public). Free admission if you just want to come and browse! Credit cards, checks and cash accepted. Click on the link below for more details.

http://www.delawarenaturesociety.org/NativePlantSale#.WuijZi7wa7Q

Ian Stewart

The global Great Backyard Bird Count took place from February 16th to the 19th and was a huge success. Despite its misleading name, participants counted every bird they saw no matter how far they were from home, with more than 6,000 bird species recorded across the world from over 160,000 checklists! Delaware Nature Society played its part with 10 people joining Joe Sebastiani and Matt Babbitt on a bird-filled tour of Port Penn Wetlands, the Aquatic Resources Education Center, Bombay Hook NWR, and Port Mahon Road, finding over 50 species in the process including a rare Tree Swallow.

Although the global comparisons are fun, what’s really fascinating is to sift through the species and checklist totals from each US state (https://ebird.org/gbbc/region/US/regions?yr=cur&m=). The top 3 in terms of species seen were California (370), Texas (358) and Florida (288) with Delaware coming in 24th with a very respectable 145 species. The top 3 in terms of checklists submitted were again California and Texas (8,113 and 6,389 respectively) and New York (6,154) with Delaware coming in 37th with a decent 709.

DNS Members enjoying a duck extravaganza at Port Penn

But wait, I hear you cry! Surely this is unfair! California, Texas and Florida are all large states with extensive oceanic coastlines and inland water bodies and because of their southern latitude have resident tropical birds that we can only dream of. Furthermore, large parts of these states have mild or even warm winters so their birdlife gets supplemented by migrants that summered much further north. California, Texas and New York all contain huge numbers of people which presumably translates to lots of birders so it’s hardly a surprise that these 3 states produce the largest numbers of checklists.

I decided to see how Delaware fared during the GBBC once you take into account our small population (ranked 45th in the nation) and size (ranked just 49th!). To do this, I simply divided the number of species seen and checklists submitted from each state by their population (in millions) and size (total land area).

Sure enough, once you control for population size (as a crude estimate of the number of birders) we jump to second in the nation!

State Species per 1M persons
1. Alaska 158
2. Delaware 152
3. Wyoming 147
50. New York 9

And when you take into account our small size, Delaware recorded the second highest number of species in the country.

State Species per 1000 square miles
1. Rhode Island 74
2. Delaware 58
3. Connecticut 24
50. Alaska 0.2

The number of checklists is also an interesting statistic although obviously they aren’t all created equal. One checklist may summarize birds seen by a large group of experienced birders during an intense 6-hour search of a large, rural, mixed-habitat wildlife preserve while another could be birds seen at an urban backyard feeder by a relative novice during a 15 minute coffee break. Still, when you account for population size, we generated the third highest number of checklists in America.

State Checklists per 1M persons
1. Vermont 1503
2. Maine 918
3. Delaware 745
50. Nevada 119

And when you take into account our small size, Delaware produced the third highest number of checklists in the US!

State Checklists per 1000 square miles
1. New Jersey 325
2. Connecticut 292
3. Delaware 285
50. Alaska 1

Admittedly, trying to boil down differences between state bird lists based on just their size or population is simplistic. The dramatic differences between states in their habitat diversity and latitude and longitude means you are never comparing like with like. For example, birders in coastal states see large numbers of seabirds and shorebirds which are hard to find further inland. Freshwater lakes or marshes in the south will have more waterbirds than those in the frozen north. Plus, even though some states are huge a large proportion of their area is inhabited by very few people let alone birders, and so only a small proportion receives coverage. I’m sure there are many more bird-related differences between states you can think of yourself.

But it’s these exact same caveats that make Delaware such a fantastic place to live if you like birds! Because we are mid-latitude we get a sprinkling of unusual birds from further north plus a few rarities from further south. We have freshwater, seawater, estuaries, lakes and ponds, marshes, plowed fields and pasture, pine woods, deciduous woods, urban habitats, suburbs and a big open sky. This diversity of habitats was probably the main reason the Delaware GBBC produced such an amazing diversity of birds despite our small population and size. To all the Delaware birders who contributed to the GBBC (and you know who you are) I say well done! We’re in the Top 3!

If you want to continue to enjoy birds, why not come along on these upcoming DNS events and bird walks?

Dinner and Owls

February 28
5:30pm
$20/$25
Coverdale Farm

Led by Jim White and Courtney McKinley. Get close up looks at the rare Long-eared Owl, and search for other owls like Screech and Great Horned Owls. Dinner and an owl presentation are included too!

Frogs and Woodcocks

March 28
5:30pm
$15/$20
Coverdale Farm

Led by Jim White.Take a walk in the evening to find chorusing frogs and see the amazing display of the American Woodcock.

Tuesday Bird Walks (April/May)

8am, Middle Run Natural Area
Free, just meet in the parking lot

Thursday Bird Walks (April/May)

8am,Ashland Nature Center
Free, just meet in the parking lot