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USGS2001

Searching for biological specimens from midwestern parks: Pitfalls and solutions

This paper describes the results of searches of herbarium and museum collections and databases for records of vertebrate and vascular plant specimens that had been collected in 15 midwestern National Park System units. The records of these specimens were previously unknown to the National Park Service (NPS). In the course of our searches, numerous obstacles were encountered that prevented us from fully completing our task. These ranged from difficulties with the way databases are structured, to poor record-keeping, to incomplete or incorrect information on the actual location of specimens within collections. Despite these problems, we are convinced that the information to be gained from such searches in invaluable, and we believe that our experience, and the recommendations we offer, may well prove instructive to others undertaking this kind of work.

Arkansas, Indiana, Iowa, Kansas, Minnesota, Missou↗
USGS1971

Biology of larval sea lampreys (Petromyzon marinus) of the 1960 year class, isolated in the Big Garlic River, Michigan, 1960-65

The early life history of the sea lamprey, from hatching to the first capture of metamorphosed individuals, is described from observations on a known-age population isolated in a tributary of southern Lake Superior. The population had its origin in the spring of 1960, when 722 sea lampreys nearing spawning condition were introduced into the Big Garlic River, Marquette County, Michigan, a stream that had previously been free of lampreys because physical barriers prevented their upstream migration. The adults constructed 206 nests and spawned in 161 of them; an estimated 774,000 larvae were hatched. The average total lengths of larvae collected in October (when yearly growth was nearly complete) in 1960-65 were 13, 39, 63, 80, 92, and 107 mm in the successive years. A specially designed inclined-plane trap, installed at the lower end of the study area to monitor the downstream movement of larval and newly metamorphosed lampreys, captured 7,562 larvae in 1962-65 (none in 1960-61). The annual catch increased sharply from 9 in 1962 to 370 in 1963, 2,847 in 1964, and 4,336 in 1965. About 90% of each annual catch was taken by June 30. Most movement was at night. A total of 5,642 larvae were marked in 1962-65 by the subcutaneous injection of an insoluble dye, to study movement and distribution; 222 were recovered as larvae through 1965 (17 in the trap and 205 with an electric shocker). The recoveries of marked lampreys, the increase in density of larvae in the farthest downstream section of the study area, and the annual catches in the trap demonstrated that a large part of the population gradually shifted downstream. On the other hand, many larvae were still within less than 1 km from the place of hatching, after more than 5 years. The capture of four recently metamorphosed sea lampreys (two males and two females), 152-172 mm long, in the fall of 1965, established the minimum age at transformation for larvae in the Big Garlic River at 5 years. Age and length (with the exception of a possible minimum length) were determined not to be critical factors in metamorphosis. The presence of larvae 65-176 mm long (mean, 107 mm) in the river in 1965 indicated that metamorphosis of lampreys in a single year class takes place over a period of years.

Technical Report↗
USGS1978

Biology of larval and metamorphosing sea lampreys, Petromyzon marinus, of the 1960 year class in the Big Garlic River, Michigan, Part II, 1966-72

The 1960 year class of sea lampreys, Petromyzon marinus , isolated in a tributary of southern Lake Superior continued to yield information on the early life history of the sea lamprey. The larval population persisted and newly metamorphosed individuals were captured from 1966 until the study was terminated in 1972. The average lengths of larvae collected in October (when yearly growth is nearly complete) in successive years from 1966 to 1972 were 111, 113, 112, 114, 121, 128, and 129 mm. The average lengths of transforming lampreys during the same years were 150, 151, 145, 143, 144, 148, and 156 mm. A gradual downstream shift of the population took place. Catches in an inclined-plane trap at the lower end of the study area increased to a peak of 13,244 in the 1968-69 migration year (September 1-August 31), and then steadily decreased. As the number of lampreys decreased in the upper sections and increased in the lower ones, the changes in density were reflected in changes in growth rates. Although the mean length of ammocetes throughout the stream was 111 mm in 1966, it had increased by 1971 to 151 and 143 mm in the upstream sections (IV and V), but to only 115 mm in the densely populated area immediately above the trap. Of a total of 9,889 larvae marked in 1962-68 to study movement and distribution, 2,045 were recovered as larvae and 1,396 as newly transformed adults. Major downstream movements of larvae occurred during high water in April and May, and of transformed lampreys in mid-October through November. Each year about 40% (range, 30-68) of the annual production of transformed lampreys migrated from the Big Garlic River system in one 12-hour period, and 82% by the end of October. The Big Garlic River study proved conclusively that metamorphosis of a single year class occurs over a considerable number of years. Newly metamorphosed individuals were captured in almost steadily increasing numbers from 1965 (age V) to the termination of the study in 1972 (age XII). Many large ammocetes were still present in the study area in 1972, and it can safely be assumed that they would have continued to metamorphose for several more years.

Technical Report↗