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Observations by Gary Fewless for Green Bay WI (Lat.N 44.51° Long. W 88.02° ), except as noted. For flowers lacking conspicuous petals or sepals I define "anthesis" as release of pollen by mature anthers.

April 2002

Observations by Gary Fewless, except as noted

Date Observation (Click on links for photos)
Apr30 We had some record high temperatures in northeastern Wisconsin on April 15 and 16, but we also had measurable snowfall on 5 days for a total of 7.5 inches (and a trace of snow on 4 more days). April showers may in fact bring May flowers, but I don't think they had snow showers in mind when that phrase was coined. Here's a graph of the April 2002 high and low temperatures and the average highs and lows for each day.
Apr29 Rufous-sided Towhee, Manitowoc County, Cooperstown area (Joel Trick).
Apr28 Winter storm for northcentral Wisconsin, Elcho had 20 inches(!) and others in the area in excess of 12 inches. Green Bay received only a trace of snow and 0.47 inches of rain.

The first Big White Trillium (Trillium grandiflorum) I've seen (just one) with fully opened flower, Baird Creek Parkway (Gary Fewless).


Wild Ginger (Asarum canadense), Field Pennycress (Thlaspi arvense) and Yellow Rocket (Barbarea vulgaris) UWGB (Gary Fewless).

Ovenbird and Wood Thrush, Rock County (Andy Paulios).

Numerous flocks of double-crested cormorant migrants, Door County, Rowley's Bay, 25th and 26th (Joel Trick).

Greater Yellowlegs, Pectoral sandpipers, Brown County (wisbirdnet).


A serious snow flurry this morning about 9 a.m., City of Green Bay (Gary Fewless).

Solitary sandpiper on our pond in evening, Manitowoc County (Joel Trick).

Northern Rough-winged Swallow, Barn Swallow, Rusty blackbird, Blue-gray Gnatcatcher, Ruby and Golden-crowned Kinglets, Spotted Sandpiper, Palm Warbler, Hermit Thrush, Brown Thrasher, Swamp Sparrow, Bay Beach Wildlife Sanctuary and Barkhausen Waterfowl Preserve, Brown County (Dave Marks).


White Birch (Betula papyrifera) and Norway Maple (Acer platanoides) in flower on UWGB. Both had been close since last week, but flowers not fully open until today.

The following trees and shrubs have "leafed out" to the point where they are giving a green cast to forests and fencerows in the City of Green Bay: American Wild Currant (Ribes americana), Bell's Honeysuckle (Lonicera xbella), Crack Willow (Salix fragilis), Sandbar Willow (Salix exigua, previously S. interior), Quaking Aspen (Populus tremuloides).

Northern Pike in the stream at Point Sauble (spawning). Pike have been active along the west shore of Green Bay since about April 12, with a few noted even earlier--I haven't been able to monitor that area closely (Gary Fewless).

White Trout-lilies (Erythronium albidum) reported in full bloom in the Madison Area; also a Spring Azure butterfly (Andy Paulios).

A late note: The Whooping Cranes (5 ultimately, I think) returned to Wisconsin April 18th.


An overnight low of 28 F produced thick ice on our birdbath. Still one lone Tree Sparrow at the feeders this morning (Gary Fewless). Here are the April tempertures to date.

The first fully opened White Trout-lily (Erythronium albidum) and Yellow Trout-lily (Erythronium americanum), UWGB (Gary Fewless). They had been close since last week, but were delayed by cool weather and snow.


We received 0.3 inches of snow after midnight last night, bringing the storm's 2 day total to 4.1 inches. Most of yesterday's snow had melted by the end of the day today.

Ruby-throated Hummingbird, Madison (wisbirdnet).

Indigo Bunting, Jefferson County (wisbirdnet).


Hairy Wood Rush (Luzula acuminata), Brown County Reforestation Camp; False Rue Anemone (Isopyrum biternatum), UWGB (Gary Fewless).

Baby Cottontail Rabbit!, Green Bay (Gary Fewless).

Marsh Marigold (Caltha palustris), and Early Buttercup (Ranunculus fascicularis) in flower, Town of Scott, Brown County (Joel Trick).

Brown Thrasher, Brown County (wisbirdnet).

Green Bay received 3.8 inches of snow in the afternoon and evening.

Tree Sparrows are nearly gone from our area for the summer. I hadn't seen one since Wednesday the 17th, but one appeared at our feeders today before the snowstorm. Joel Trick in Manitowoc County had not seen one since the 14th.


Swamp Red Currant (Ribes triste), Bristly Buttercup (Ranunculus hispidus), Purple Spring-cress (Cardamine douglassii), Dutchman's Breeches (Dicentra cucullaria) and Chinese Juniper (Juniperus chinensis--this is planted)) in flower UWGB. Small-flowered Crowfoot (Ranunculus abortivus) in flower High Cliff State Park, Calumet County (Gary Fewless).


Yellow Trout Lily (Erythronium americanum) in flower, Manitowoc County, Town of Cooperstown (Joel Trick).

The very warm tempertures earlier in the week, and the heavy rain yesterday caused severe flooding in Michigan's upper peninsula. Iron River and other locations have been designated "disaster" areas by the governor of Michigan.


"Wood Tick" (Dog Tick) out in Marinette Co, Town of Peshtigo (Dave Marks).

Cottonwood (Populus deltoides) in flower (anthesis), UWGB (Gary Fewless). A few trees in lawns were in flower yesterday, but the tree noted here is in a wetland. It flowered April 25 last year, which is the average for that individual over the last 16 years. We are averaging about a week earlier than last year for most phenology items on UWGB--but that can change quickly if the weather changes.

Meadow Willow (Salix petiolaris) in flower (anthesis), UWGB; Box Elder (Acer negundo) in flower, City of Green Bay, (Gary Fewless).

Suckers spawing in Mahon Creek (Gary Fewless) .

Green Heron, Barn Swallows, City GB (wisbirdnet).


After the cold March weather delayed development of the plants, this blast of warm air has resulted in a very rapid sequence of events. The high temperature on 4/15 was 84 F which tied the record, and on 4/16 the high was 83. The average high for this time of year is 54.

Here are some new species in flower on the UWGB campus: Long-stalk sedge (Carex pedunculata), Spring Beauty (Claytonia virginica), Prairie Willow (Salix humilis), Slippery Elm (Ulmus rubra), Common Horsetail (Equisetum arvense) . Also the leaves of American Wild Currant (Ribes americana) and Bell's Honeysuckle (Lonicera xbella) are rapidly expanding, to give the first faint green tone to our upland forests.

Bloodroot (Sanguinaria canadensis) in flower Manitowoc County (Joel Trick) and Brown County, UWGB (Gary Fewless).

Broadwing Hawks noted by several people along Lake Michigan (Andy Paulios), Waukesha County, Dane County (wisbirdnet), Brown County (Dave Marks).

Yellow-headed Blackbird, Brown County, Sensiba Wildlife Area (Andy Paulios).

White-throated Sparrow, Brewer's Blackbird, Brown County, Bay Beach Wildlife Sanctuary (Dave Marks).


Pennsylvania sedge (Carex pensylvanica) in flower (dispersing pollen), UWGB (Gary Fewless).

Numerous American Toads calling on Prairie Pond, UWGB. There were a few yesterday (Gary Fewless).

Chipping Sparrow, Lakewood, Oconto County (Steve Janke).

Forsythia in flower (cultivated) City of Green Bay (Gary Fewless).

MyrtleWarbler, Greater Yellowlegs, both Kinglets, Hermit Thrush, a few Loons, Pied-billed Grebes,Savannah & Vesper Sparrows, Eastern Meadowlark, Pine Warbler, Eagle River Area (Jim Baughman).

White-throated Sparrow, City of Green Bay (Dave Marks) .


New in flower: Shepherd's Purse (Capsella bursa-pastoris), Ragwort (Senecio vulgaris), Western Androsacae (Androsace occidentalis), Large-toothed Aspen (Populus grandidentata), Marsh Marigolds (Caltha palustris), American Elm (Ulmus americana) all on UWGB campus (Gary Fewless).

The first female Red-winged Blackbirds returned to our feeders (the males returned March 9)

Bloodroot (Sanguinaria canadensis) in flower, Shawano (Joel Whitehouse).

Yellow-rumped Warbler, Elton, Langlade County (Steve Janke).

Leopard Frogs, Spring Peepers, American Toads calling, west shore of Green Bay, Oconto and Brown Counties (Steve Price).

Swamp Sparrow, a coastal wetland near Little Suamico (Steve Price).

American Toads calling!!! Blue-gray Gnatcatchers, Cook Arboretum, Janesville, Rock County, also Chipping Sparrows. (Andy Paulios).

Apr14 Pussy Willow (Salix discolor), female aments fully open, but male aments are not yet mature, Bellevue, Brown County (Gary Fewless).

First Chipping Sparrow of the year, Purple Finches singing, a Common Redpoll, and the first Turkey heard gobbling. Slate-colored Juncos seem very abundant, as are Yellow-rumped Warblers. Fox Sparrow, Hermit thrush, Tree swallow. Also saw several Garter Snakes today, and a Compton's Tortoiseshell - the first one I've seen here. Another significant first is the first flower open on Sharp-lobed Hepatica Hepatica acutiloba. Cooperstown Area, Manitowoc Co, (Joel Trick).

At least 8,000 Scaup, hundreds of Redheads, and fewer
Canvasbacks on Green Bay, observed from Point Sauble. Also White Pelican,
Cormorants, Bufflehead
and Common Merganser. Sandhill Cranes, Blue winged
and Green winged Teal, Northern Shoveler and Mallards in the lagoon. Other
"notables": Snipe winnowing, Bald Eagle, Eastern Bluebird, Swamp Sparrow.
Leopard Frogs in full chorus and Cicindela repanda (a tiger beetle) active
on the beach, Point Au Sauble, Brown County (Joan Berkopec and Ron Eichhorn).

Mourning Cloak butterfly, City Green Bay (Mike Draney), Mourning Cloaks also at Brown County Park, Town of Hobart, Brown Co (Gary Fewless).

Beaked Hazel(Corylus cornuta) in flower City GreenBay, planted; American Hazelnut (Corylus americana) in flower, Brown Co, UWGB (Gary Fewless).

Snow Trillium (Trillium nivale) in flower, Brown County (Gary Fewless).

Forster's Tern Walworth County (wisbirdnet).


Wood Frogs calling and Ruffed Grouse drumming repeatedly, Brown County, Peters Marsh area near the bay of Green Bay (Gary Fewless). Speckled alder (Alnus rugosa) is widely in flower in this area.

Quaking Aspen (Populus tremuloides) in flower (anthesis). Also Dandelion (Taraxacum officinale), Chickweed (Stellaria media) in flower at the base of a south-facing brick wall, all at UW-Green Bay (Gary Fewless). Plants adjacent to south-facing walls often flower very early because they get a heat "subsidy" from sunlight reflected from the wall and possibly also from heat passed directly from the building. Dandelions in the open, in lawns, etc will probably not flower for a couple of weeks yet and the peak of flowering in lawns is usually well into May.

Purple Martin, City of Green Bay (wisbirdnet).

Green Darners (Odonata), Brown Thrashers, Janesville (Andy Paulios).


Gadwall, American Wigeon, Blue-winged Teal, Green-winged Teal, Eastern Phoebe, Sora all seen at Point au Sauble, Brown County (Rusty Japuntich).

Fox Sparrows, Song Sparrows, Yellow-bellied Sapsucker, Antigo, WI, Langlade Co (wisbirdnet).

Barn Swallow, Field Sparrow, Savannah Sparrow, Pectoral Sandpiper, Madison (Andy Paulios).

Brown Creeper and Wood frogs calling, Manitowoc County, Town of Cooperstown (Joel Trick).

Eastern Phoebe, Elton, Langlade County (Steve Janke).

Field Sparrows, City of Green Bay (Wisbirdnet).


Yellow-bellied Sapsucker, Elton, Langlade County (Steve Janke).

Great Egrets back on Green Bay (Tom Erdman).

Tree Swallows, Great Blue Herons, Green Herons and American Woodcock, Rhinelander, Oneida County (wisbirdnet).

Spring Peepers calling and a big Snapping Turtle out and about, Happy Hollow Park, Janesville, WI (Andy Paulios).

Eastern Phoebe, Manitowoc County, Town of Cooperstown (Joel Trick).


This was the first really spring-like day of the year. A high temperature of only 51 F at the Green Bay weather station, but with a little sunshine it definititely felt Spring-like (have I lowered my standards?) (Gary Fewless).

Tree Swallow, Yellow-rumped Warbler, Fox Sparrow, Song Sparrow, Point Au Sauble, Brown County. Also Canada Geese on nest. (Rusty Japuntich).

Northern Flicker, UWGB (Dave Marks).

Garter Snake, Fonferek Glen, Brown County (Angella Sette).

Mourning Cloak butterfly, Fonferek Glen, Brown County (Angella Sette).

First Parson spider (Gnaphosidae: Herpyllus ecclesiasticus, a ground spider), the surest arachnid harbinger of spring I know, City of Green Bay (Mike Draney). They show up in houses, but not until spring is underway.

Virginia Rail and Sora reported for Madison area (wisbirdnet).

Spring Peepers calling on Green Bay in Brown County (Gary Fewless) and Oconto County (Tom Erdman).


Red-backed Salamander, UWGB (Steve Price).

Eastern Meadow Lark and Fox Sparrows, UWGB (Dave Marks).

Earthworms on the driveway, Manitowoc County and City Green Bay (Joel Trick).

Great Egret, Manitowoc Co, Town of Cooperstown (Joel Trick).


Ice is off Prairie Pond, UWGB (Gary Fewless). Last year the ice was off 04/08, but it has been as early as 02/27 (1998) and as late as 0417 (1996). The pond froze last Fall on 12/18 so it was ice-covered for 109 days. The longest ice-covered period was 145 days in 1996/97 and the shortest was 107 days (1997/1998). I began keeping this information in 1996 so this is only the 6th winter for which I have data.

Yellow-bellied sapsucker, Fox sparrow, Ruby-crowned Kinglet, Hermit thrush, Bay Beach Wildlife Sanctuary, Green Bay (wisbirdnet).

Yellow-bellied Sapsucker , Manitowoc County, Cooperstown area, (Joel Trick).

The following birds were noted in the City of Green Bay, near the mouth of the Fox River: Double-crested Cormorants (in large numbers), American White Pelican, Common Loon, Tree Swallow, Fox Sparrows, and Flickers (wisbirdnet).

Dark-eyed Junco (Oregon race) at a feeder, Clintonville, Waupaca County (Steve Janke).

Brown Creeper, City of Green Bay (Vicki Medland).


New seedlings of Common Knotweed (Polygonum aviculare) have begun to grow along sidewalks, paths, cracks in pavement, etc., City of Green Bay (Gary Fewless). This is the earliest annual species to become visible in the Spring, although a few others are close, including Spotted Touch-me-not (Impatiens biflora) in springy areas.

Belted Kingfisher, Shawano (Joel Whitehouse).

Painted Turtles and Snapping Turtles active and basking, Barkhausen Wildfowl Preserve, Brown County (Steve Price).

First report of a 13-lined ground squirrel, Barkhausen Wildfowl Preserve, Brown County (Steve Price).

White Pelicans (7) reported at Horicon Marsh (wisbirdnet).


Eastern Bluebird, Shawano (Joel Whitehouse).

Canada Goose on eggs, Janesville, Rock County (Andy Paulios).

Large flock of migrant Double-crested Cormorants, Lake Koshkonong, Rock County (Andy Paulios).

Wild Leek (Allium tricoccum) and Spring Beauty (Claytonia virginica) have initiated growth -
Claytonia leaves mostly fully developed, Allium emerged 1/2 to 1 inch, Manitowoc County, Cooperstown area (Joel Trick). These species are in about the same status at UWGB and elsewhere in the City of Green Bay area; Alliun canadense is also up about an inch (Gary Fewless).


Speckled Alder (Alnus rugosa) in flower, City of Green Bay (Gary Fewless). This is one of the earliest flowering individuals of this species of which I am aware. Other Speckled Alder plants I have seen are not yet in flower. The average first flowering date for this individual has been about 03/28 over the last 17 years.

Year 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02
Date 03/30 03/21 03/31 03/31 03/15 03/27 04/02 04/10 03/31 03/16 04/10 04/02 03/26 03/24 03/07 04/08 0404

As the male catkins of Alder open, they increase in length to at least double their winter size and they become visibly flexible. Since it can be difficult to determine exactly when such a process is complete, I use the dispersal of pollen as the test of flowering. If you can reach the catkins you can tap them with your finger to see if the yellow pollen has been released. If you can't reach them, you can usually jar the trunk a little with your hand and watch the pollen fly out of the catkins.

Eastern Chipmunk out, Lakewood, Oconto County (Steve Janke).

In spite of a cool night and a few more snowflakes this morning, there were fresh earthworm castings in muddy soil along one of the sidewalks at UWGB. These sites get an energy subsidy from the sidewalk so this is not an indication that earthworms are generally "up".

Tree Swallows reported in Wausau , Marathon County (wisbirdnet).

There is obvious swelling of the buds of many tree and shrub species and there is new growth on some of the earlier herbaceous plants on soil at edges and in cracks of sidewalks and streets. Today I can see very small new leaves of Pineapple Weed (Matricaria matricarioides) in a gravelly parking area on the UWGB campus.


More snow during the morning hours. March had at least a trace of snow on 20 of 31 days and so far April is 2 for 2.

Tree Swallows, Janesville, Rock County (Andy Paulios).


Part of our April Fools day experience this year is more snow. Development of new spring growth will be delayed a bit.

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Last updated on May 20, 2015