Lake Superior produced an impressive (by Minnesota standards) peak of 12 Red-throated Loons in late May, but the peak count of Horned Grebes was paltry compared to the 1970s. Horned Grebe has been virtually extirpated as a breeding species in the state and systematic surveys are now needed to determine their true status in migration. For the second consecutive spring, good numbers of Snowy Egrets were reported. Two of this season's three Little Blue Herons were unexpectedly found in the northwest region.

For the sixth consecutive spring, Cattle Egrets remained scarce compared to the total of 105+ in 1993. A pair of White-faced Ibis in Dakota County was conveniently located in front of a local market for four days in early May.

Record high numbers of the Ross's Goose migrated through western Minnesota this spring, a bonanza for birders but transmogrifying for the tundra. Even though the Trumpeter Swan has been designated a Regular species as of 1 January 1999, observers are encouraged to report exact locations, number of adults and young, and all banding data. Field identification of Trumpeter vs. Tundra Swan remains vexing and details are requested for swans seen at unexpectedly early or late dates, especially
for singles or small groups. Two unusually warm winters in a row has certainly skewed our concept of “normal” waterfowl migration. But nothing can skew more than that first state record Smew!

Who among us has ever dreamed of discovering a Swallow-tailed Kite while fishing for walleye in Minnesota? Many dozens of people eventually saw this beautiful kite, thanks to Cindy and Vern Krienke. Frank Nicoletti and Dave Carman conducted the third annual spring census of raptor migration at Enger Tower in Duluth (see Table 1); highlights included an unexpected Swainson's Hawk and good numbers of Golden Eagles among the total of 6,624 raptors for the season (7,795 last spring).

Like the last two springs, there were only two reports of the Common Moorhen. Shorebird migration in most regions was relatively late and many species were reported in low numbers. The only Piping Plovers were in Duluth, including a pair on Hearding Island for four days that exhibited nesting behavior, but hopes were dashed when the birds disappeared after the first of June. The number of American Avocets was disappointing, but a good flight of Hudsonian Godwits was noted. The peak count (159) of Wilson's Phalaropes in northwest Minnesota was lower than usual. Most unexpected was the male Red Phalarope discovered by a Minnesota Birding Weekends group on Lake Superior. This is only the second time this Casual species has been found in spring.

Another spring record of a jaeger in Duluth! Although expected in fall, jaegers have now been reported in eight out of the past ten spring migrations. For the first time since 1993, a Little Gull was found in Duluth during spring migration. For the second consecutive spring, an adult Black-headed Gull was found in south-central Jackson County. Gull migration was uneventful compared to last spring. Relatively few Thayer's Gulls and no Iceland Gulls were found. The dark-backed gull species were also scarce. An Arctic Tern was seen in Duluth, where this Accidental species has occurred during six previous migrations.

Only one year ago, Minnesota's first Eurasian Collared-Dove was found in Big Stone County; this season's record is the state's fifth! Long–eared Owls were found in good numbers and after two consecutive years of decline during spring migration, no fewer than 45 Short–eared Owls were reported. Nocturnal surveys for calling Boreal Owls in northeastern Minnesota found 15 singing males (10 last spring).

Two Scissor-tailed Flycatchers were more than expected, but equalled the number found last spring. Reports of the Loggerhead Shrike appear stable over the past few spring migrations. The three records of White-eyed Vireo were unprecendented for one season and stay tuned for summer! Unlike most occurrences in Minnesota, the Rock Wren in Houston County was seen by many observers and stayed for more than a day, perhaps because it found itself in a rock quarry. For the third consecutive spring, no fewer than seven Northern Mockingbirds were discovered.

In contrast to relatively late arrivals among the flycatchers, wrens, bluebirds, and thrushes, warblers as a group arrived earlier than usual and in good numbers. Steve Carlson examined 20 years of migration data from Hennepin County and found that he observed a greater variety of warblers during the first few days of May than ever before (including 17 species on 5/4). Other peaks included 20 species in Jackson County on 5/13 (PS), 19 species in a single Goodhue County location on 5/13 (DZ), 20+ species in Kandiyohi County on 5/15 (RJF), and 22 species in Anoka County on 5/15 (DZ). Dan Floren scoured Meeker County this spring and found so many first county records, especially among the warblers, that his well-documented reports were dubbed “Another First by Floren.”

Highlights among the many interesting warbler reports included the pair of Yellow-throated Warblers at Sibley State Park, where Minnesota's first nest was found on 29 May 1997 (The Loon 70:230–232). There were no sightings here in 1998, but one or more had been present in the park for four consecutive years between 1994 and 1997. The Prothonotary Warbler was reported in 13 counties as far north as Kanabec. An amazing five Worm-eating Warblers were found, three in the southeast region where most expected, plus two in Kandiyohi County. No fewer than five Kentucky Warblers were discovered, including first county records for Jackson and Kandiyohi. Hooded Warblers were also reported more frequently than usual and even showed up in two North Shore locations! One additional species sometimes considered a “southern” warbler, the Louisiana Waterthrush, was reported within range but its numbers were apparently up. As outlined by Karl Bardon elsewhere in this issue, increased numbers of these warblers may have been associated with the unprecedented influx of Summer Tanagers into Minnesota.

All records of the Western Tanager still require documentation for publication in the seasonal report; two of this spring's three reports had details. Another Field Sparrow was found along the North Shore (there were two such records last spring) and Grasshopper Sparrows were located in Duluth and Grand Marais. Tom Boevers not only found the first Henslow's Sparrow for Rice County, but went on to find them in another Rice County location! The initial discovery was at Faribault WMA, where follow-up visits found up to eight birds. Perhaps this will prove to be a reliable location for this species in Minnesota.

For the first time in many years, this migration report was prepared by one individual rather than the usual team of compilers. It is hoped that this approach will provide more consistency within the report itself, and more continuity with the winter and summer seasons. The data are also presented with an emphasis on peak numbers and timing of peak migration. As the data are compiled, the earliest and latest dates for this season are compared to recent median arrival and departure dates. Unusual dates will still be published in the seasonal report and will generally be accompanied by additional migration dates and/or interpretive data, in order to place these dates in perspective.

Remarks such as “earlier than usual” or “arrived on time” in the species accounts refer to comparisons with the recent median arrival or departure dates for the past 13 years at this season. These data were calculated by Paul Budde from early and late dates compiled by Bob Janssen and Paul. The earliest and latest dates for each species during every spring and fall migration will be maintained in a database, and the median arrival and departure dates will eventually be based on 20 or more years of migration, rather than the most recent 13 years. There are tentative plans to periodically publish median dates, extreme dates, and annual arrival and departure dates in an occasional paper for future research purposes. Comments on these changes to the format and focus of this report are most welcome.

Unconfirmed and Undocumented Reports: Clark's Grebe in Traverse County, several Mississippi Kites, Whooping Crane in Kandiyohi County, Rufous Hummingbird in Ramsey County, Western Tanager in Crow Wing County, Spotted Towhee in Rice County. This section does not include records found Unacceptable by the Minnesota Ornithological Records Committee.

Temperature and Precipitation Summary: Temperatures statewide were two to four degrees above the long-term average for all three months. March was especially warm in the northern regions, where it was between four and six degrees above normal. These regions continued to be at least two degrees warmer than normal throughout the remainder of the season. The southeast region was about three degrees warmer than normal, during all three months.

Statewide, precipitaion was close to average during March and April, except for a few wet spots. The central regions received the most precipitation during March. The southern regions, especially the south-central (3.76 inches above normal) and the southeast (2.85 inches above normal) were the only wet areas in April. The month of May was significantly wetter than usual in all regions except the northeast, west-central, and southwest. This was especially true for the north-central (3.15 inches above normal) and east-central (3.35 inches above normal) regions.

Acknowledgments: Many thanks to Dave Benson and Wally Swanson for their help as compilers of “The Season” over the past few years. Frank Nicoletti and Dave Carman contributed data from their spring census of raptors at Enger Tower in Duluth. Kim Eckert and Anthony Hertzel summarized reports called in to the MOU “hotlines” in Duluth and the Twin Cities, respectively. I would like to thank and acknowledge Karl Bardon in his new role as co-editor of “The Season.” His review and commentary greatly improved this spring's report.

With deep regret we note that this represents the final season for Eugene Ford and Ray Glassel, both of whom died during the summer of 1999. Their contributions will be greatly missed.