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BOTANICAL EVALUATION OF THE GOAT ISLAND COMPLEX, NIAGARA FALLS, NEW YORK |
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NUMERICAL ASSESSMENT OF FLORAL CHANGES ON GOAT ISLAND, EXCLUSIVE OF THE ADJACENT ISLANDS A distortion built into the figures below is caused by defining Goat Island as including island peripheral areas such as the dolomite flats on the island's south side, the limestone ledge at the edge of Terrapin Point and the base of Goat Island. These habitats are the wild habitats, isolated from maintenance activities and visitor impact. These relatively species-rich areas inflate the number of taxa presently recorded for Goat Island proper, which is profoundly impoverished by elimination of much species habitat. The figures reflect presence of marginally surviving species. The highest diversity occurs on the extreme periphery of the Goat Island platform, especially the populations of native species. These extremities are refugia from habitat elimination and alteration taking place on the island. Note that many of the species "new" to Goat Island as a result of recent collection were noted by Day as occurring close by, perhaps on the mainland shorelines of New York and Ontario. They are not new to the vicinity, and, if common, may have simply been overlooked or disregarded if they occurred on Goat Island. Another possibility may be that, since the mainland was disturbed at an early date - by at least a century before Day's catalogue - many weedy taxa perhaps did not occur on the Island in Day's time, but did on the mainland. Day provided a great service by cataloguing the larger flora related to the cataract environment, of which Goat Island is only a part. Tabulations below are for total recorded and reported number of genera and species. This figure is broken down to number of native and alien genera and species. These figures are in turn divided into number of native and alien genera and species reported up to 1940, then number of native and alien genera and species recorded since 1985. Numbers of native and alien genera and species are given for taxa extirpated or not reported since 1940, and numbers established or recorded since 1985. "Native" refers to species that have evolved in eastern North America and were believed present in the Niagara Frontier Region before European settlement, and are based on tabulations by Zander and Pierce (1979). "Alien" refers to species introduced into the region from other floristic regions in North America and other continents. These latter are what are commonly referred to as weeds and are mainly horticultural species. These are primarily introduced by accident in garden soils, lawns or deliberately with horticultural intent. The designations native and alien merely refer to the point of origin of a species for a particular area, and provide little biological information. However, some generalities may be made. Some species are typical of deep woods and others of open meadows. Speaking broadly, the first are generally associated with climax or near-climax habitats of shade and moisture, the second with disturbance and successional plant communities with sun and dryness. Biological strategies, such as those for pollination, seed dispersal, individual longevity, period of fruit ripening, number of offspring, will differ considerably between climax and successional species. It is unlikely that climax species from one vegetational type will persist after introduction in climax habitats of another vegetational type. An exception may be climax tree species of one region, perhaps of the same genus as the climax tree species of another, becoming established and creating a forest in which it dominates. An example might be the new Niagara gorge forests in which Sugar Maple (Acer saccharum), the climax forest tree of the region is being replaced after disturbance by forests of alien maples composed of Sycamore Maple (Acer pseudoplatanus), Norway Maple (Acer platanoides), and Box Elder (Ash-leaved Maple, Acer negundo). It is the opportunistic, successional species of meadows, woods boundaries, paths and pastures in their native regions that generally persist when introduced into similar habitats in other regions. Generally, habitats associated with high disturbance rates, such as lawns and gardens, pavement boundaries and so forth, mimic habitat conditions favoring successional species. Such species, when introduced, tend to become established. With increase in disturbance of the primitive or climax woods through the past century comes a loss of climax species - all native, and an increase in the representation of alien taxa - but primarily the successional species of regions beyond the Niagara Frontier Region. Statistics showing ever higher numbers of alien taxa on Goat Island correspond with increasing destruction of native habitat. If alien taxa were disappearing, there would be an indication that the native habitat was being allowed to recover or regenerate. This is not happening. The single major source of disturbance affecting the following statistics is and has been maintenance policy since 1885. The following statistics would form the basis for monitoring the restoration or continued deterioration of native habitat on Goat Island. In the table given below: G = Genus or Genera; S = species HISTORIC REPORTS Family TOTAL Total Total Pre-1940 native alien native alien G S G S G S G S G S ACANTHACEAE 1 1 1 1 0 0 1 1 0 0 ERICACEAE 1 9 1 5 0 4 1 4 0 0 AMARYLLIDACEAE 1 1 0 0 1 1 0 0 0 0 ANACARDIACEAE 1 4 1 4 0 0 1 3 0 0 APOCYNACEAE 1 1 0 0 1 1 0 0 1 1 ARACEAE 2 3 2 3 0 0 2 3 0 0 ARALIACEAE 3 4 2 3 1 1 2 3 0 0 ARISTOLOCHIACEA 1 1 1 1 0 0 1 1 0 0 ASCLEPIADACEAE 1 3 1 3 0 0 1 3 0 0 BALSAMINACEAE 1 2 1 2 0 0 1 2 0 0 BERBERIDACEAE 3 3 2 2 1 1 2 2 1 1 BETULACEAE 5 8 5 7 0 1 5 7 0 0 BIGNONIACEAE 1 1 0 0 1 1 0 0 0 0 BORAGINACEAE 4 5 2 2 2 3 1 1 2 3 BUTOMACEAE 1 1 0 0 1 1 0 0 0 0 CAESALPINIACEAE 1 1 0 0 1 1 0 0 0 0 CAMPANULACEAE 1 3 1 2 0 1 1 2 0 0 CAPRIFOLIACEAE 4 11 4 6 0 5 4 6 0 2 CARYOPHYLLACEAE 7 9 1 1 6 8 1 1 3 4 CELASTRACEAE 2 3 2 2 0 1 2 2 0 1 CHENOPODIACEAE 2 3 2 2 0 1 1 1 0 1 COMPOSITAE 30 70 18 48 12 22 17 44 6 10 CONVOLVULACEAE 2 3 2 2 0 1 0 0 0 0 CORNACEAE 1 7 1 6 0 1 1 6 0 0 CRASSULACEAE 1 1 0 0 1 1 0 0 1 1 CRUCIFERAE 11 15 3 5 8 10 3 5 1 1 CUPRESSACEAE 2 3 2 3 0 0 2 3 0 0 CYPERACEAE 3 19 3 19 0 0 3 12 0 0 DIPSACACEAE 1 1 0 0 1 1 0 0 0 0 ELAEAGNACEAE 1 1 1 1 0 0 1 1 0 0 EQUISETACEAE 1 2 1 2 0 0 1 2 0 0 ERICACEAE 4 4 4 4 0 0 4 4 0 0 EUPHORBIACEAE 1 1 0 0 1 1 0 0 1 1 FABACEAE 10 16 4 7 6 9 4 7 3 4 FAGACEAE 3 8 2 6 1 2 2 4 0 0 FUMARIACEAE 1 2 1 2 0 0 1 2 0 0 GENTIANACEAE 1 1 1 1 0 0 1 1 0 0 GERANIACEAE 1 3 1 2 0 1 1 2 0 0 GRAMINEAE 24 39 15 20 9 19 11 13 2 5 HALORAGACEAE 1 1 1 1 0 0 0 0 0 0 HIPPOCASTANACEAE 1 3 0 0 1 3 0 0 1 1 HYDRANGEACEAE 1 1 0 0 1 1 0 0 0 0 HYDROPHYLLACEAE 1 1 1 1 0 0 1 1 0 0 HYPERICACEAE 1 2 1 1 0 1 1 1 0 1 IRIDACEAE 2 2 2 2 0 0 1 1 0 0 JUGLANDACEAE 2 3 2 3 0 0 2 3 0 0 JUNCACEAE 1 6 1 6 0 0 1 3 0 0 LABIATAE 15 18 9 10 6 8 8 9 7 7 LAURACEAE 1 1 1 1 0 0 1 1 0 0 LEMNACEAE 1 1 1 1 0 0 0 0 0 0 LILIACEAE 12 16 11 14 1 2 10 14 1 1 LIMNANTHACEAE 1 1 1 1 0 0 1 1 0 0 LOBELIACEAE 1 2 1 2 0 0 1 2 0 0 LYTHRACEAE 1 1 0 0 1 1 0 0 0 0 MAGNOLIACEAE 1 1 1 1 0 0 1 1 0 0 MALVACEAE 1 1 1 0 0 1 1 0 0 1 MENISPERMACEAE 1 1 1 1 0 0 0 0 0 0 MORACEAE 1 2 1 1 0 1 1 1 0 1 NAJADACEAE 1 1 1 1 0 0 1 1 0 0 OLEACEAE 4 6 1 3 3 3 1 2 1 1 ONAGRACEAE 3 5 3 4 0 1 3 3 0 1 OPHIOGLOSSACEAE 1 1 1 1 0 0 1 1 0 0 ORCHIDACEAE 2 2 1 1 1 1 1 1 1 1 OROBANCHACEAE 1 1 1 1 0 0 1 1 0 0 OSMUNDACEAE 1 1 1 1 0 0 1 1 0 0 OXALIDACEAE 1 1 1 1 0 0 1 1 0 0 PAPAVERACEAE 1 1 1 1 0 0 1 1 0 0 PHRYMACEAE 1 1 1 1 0 0 1 1 0 0 PHYTOLACCACEAE 1 1 1 1 0 0 1 1 0 0 PINACEAE 4 7 2 2 2 5 2 2 1 3 PLANTAGINACEAE 1 3 1 1 0 2 1 1 0 1 PLATANACEAE 1 1 1 1 0 0 1 1 0 0 POLEMONIACEAE 2 2 2 2 0 0 2 2 0 0 POLYGONACEAE 2 9 1 5 1 4 0 0 0 0 POLYPODIACEA 10 11 10 11 0 0 9 10 0 0 PORTULACACEAE 2 3 1 2 1 1 1 2 0 0 PRIMULACEAE 3 5 1 1 2 2 1 1 1 1 RANUNCULACEAE 7 18 7 15 0 3 6 12 0 2 RHAMNACEAE 1 2 0 0 1 2 0 0 0 0 ROSACEAE 12 35 12 23 0 12 12 21 0 6 RUBIACEAE 4 10 4 9 O 1 3 7 0 1 SALICACEAE 2 15 2 10 0 5 2 9 0 1 SANTALACEAE 1 1 1 1 0 0 1 1 0 0 SAURURACEAE 1 1 1 1 0 0 1 1 0 0 SAXIFRAGACEAE 6 8 5 6 1 2 5 5 0 0 SCROPHULARIAC 11 16 8 9 3 7 7 7 2 4 SELAGINELLACEAE 1 1 1 1 0 0 1 1 0 0 SOLANACEAE 3 5 2 2 1 3 1 1 1 1 TAXACEAE 1 1 1 1 0 0 1 1 0 0 THYMELAEACEAE 2 2 1 1 1 1 1 1 1 1 TILIACEAE 1 2 1 1 0 1 1 1 0 0 TYPHACEAE 1 2 1 2 0 0 0 0 0 0 ULMACEAE 2 3 2 3 0 0 2 2 0 0 UMBELLIFERAE 11 14 9 11 2 3 8 10 1 1 URTICACEAE 2 2 2 2 0 0 2 2 0 0 VERBENACEAE 1 2 1 2 0 0 1 1 0 0 VIOLACEAE 2 10 2 9 0 1 2 8 0 0 VITACEAE 2 6 2 4 0 2 2 3 0 2 /////////////////////////////////////////////////////////// Non-historic Historic New records Family (1988 flora) records since 1940 Present Absent (1988) native alien native alien native alien G S G S G S G S G S G S ACANTHACEAE 0 0 0 0 1 1 - - - - - - ACERACEAE 1 3 0 4 - 2 - - - 1 - 4 AMARYLLIDACEAE 0 0 1 1 - - - - - - 1 1 ANACARDIACEAE 1 3 0 0 - 1 - - - 1 - - APOCYNACEAE 0 0 1 1 - - - - - - - - ARACEAE 1 1 0 0 1 2 - - - - - - ARALIACEAE 1 1 1 1 1 2 - - - - 1 1 ARISTOLOCHIACEAE 0 0 0 0 1 1 - - - - - - ASCLEPIADACEAE 1 1 0 0 - 2 - - - - - - BALSAMINACEAE 1 1 0 0 - 1 - - - - - - BERBERIDACEAE 1 1 1 1 1 1 - - - - - - BETULACEAE 3 3 0 1 2 4 - - - - - 1 BIGNONIACEAE 0 0 1 1 - - - - - - 1 1 BORAGINACEAE 1 1 1 1 1 1 1 2 1 1 - - BUTOMACEAE 0 0 1 1 - - - - - - 1 1 CAESALPINIACEAE 0 0 1 1 - - - - - - 1 1 CAMPANULACEAE 1 0 0 1 - 2 - - - - - 1 CAPRIFOLIACEAE 4 4 0 5 - 2 - - - - - 3 CARYOPHYLLACEAE 0 0 5 7 1 1 1 2 - - 2 3 CELASTRACEAE 1 1 0 0 1 1 - 1 - - - - CHENOPODIACEAE 2 1 0 1 - 1 - - 1 1 - - COMPOSITAE 12 21 11 19 5 27 1 2 1 4 6 12 CONVOLVULACEAE 2 2 0 1 - - - - 2 2 - 1 CORNACEAE 1 5 0 1 - 1 - - - - - 1 CRASSULACEAE 0 0 0 0 - - 1 1 - - - - CRUCIFERAE 1 2 8 10 2 3 - - - - 6 9 CUPRESSACEAE 1 1 0 0 1 2 - - - - - - CYPERACEAE 3 10 0 0 - 9 - - - 7 - - DIPSACACEAE 0 0 1 1 - - - - - - 1 1 ELAEAGNACEAE 0 0 0 0 1 1 - - - - - - EQUISETACEAE 1 1 0 0 - 1 - - - - - - ERICACEAE 0 0 0 0 4 4 - - - - - - EUPHORBIACEAE 0 0 1 1 - - - - - - - - FABACEAE 1 0 6 9 3 7 - - - - 3 5 FAGACEAE 2 5 1 2 - - - - - 1 1 2 FUMARIACEAE 1 2 0 0 - - - - - - - - GENTIANACEAE 1 1 0 0 - - - - - - - - GERANIACEAE 1 1 0 1 - 1 - - - - - 1 GRAMINEAE 8 9 8 18 7 11 1 1 4 7 7 14 HALORAGACEAE 1 1 0 0 - - - - 1 1 - - HIPPOCASTANACEAE 0 0 1 3 - - - - - - - 2 HYDRANGEACEAE 0 0 1 1 - - - - - - 1 1 HYDROPHYLLACEAE 0 0 0 0 1 1 - - - - - - HYPERICACEAE 1 0 0 1 - 1 - - - - - - IRIDACEAE 1 1 0 0 1 1 - - 1 1 - - JUGLANDACEAE 2 2 0 0 - 1 - - - - - - JUNCACEAE 1 3 0 0 - 3 - - - 3 - - LABIATAE 5 6 4 5 4 4 3 3 1 1 - 1 LAURACEAE 1 1 0 0 - - - - - - - - LEMNACEAE 1 1 0 0 - - - - 1 1 - - LILIACEAE 4 7 2 2 6 7 - - - - 1 1 LIMNANTHACEAE 0 0 0 0 1 1 - - - - - - LOBELIACEAE 0 0 0 0 1 2 - - - - - - LYTHRACEAE 0 0 1 1 - - - - - - 1 1 MAGNOLIACEAE 1 1 0 0 - - - - - - - - MALVACEAE 1 0 0 1 - - - - - - - - MENISPERMACEAE 1 1 0 0 - - - - 1 1 - - MORACEAE 1 0 0 1 - 1 - - - - - -_ NAJADACEAE 0 0 0 0 1 1 - - - - - - OLEACEAE 1 2 3 3 - 1 - - - 1 2 2 ONAGRACEAE 3 4 0 1 - - - - - 2 - - OPHIOGLOSSACEAE 0 0 0 0 1 1 - - - - - - ORCHIDACEAE 0 0 1 1 1 1 - - - - - - OROBANCHACEAE 0 0 0 0 1 1 - - - - - - OSMUNDACEAE 0 0 0 0 1 1 - - - - - - OXALIDACEAE 1 1 0 0 - - - - - - - - PAPAVERACEAE 1 1 0 0 - - - - - - - - PHRYMACEAE 0 0 0 0 1 1 - - - - - - PHYTOLACCACEAE 1 1 0 0 - - - - - - - - PINACEAE 2 2 2 5 - - - - - - 1 2 PLANTAGINACEAE 1 0 0 2 - 1 - - - - - 1 PLATANACEAE 1 1 0 0 - - - - - - - - POLEMONIACEAE 0 0 0 0 2 2 - - - - - - POLYGONACEAE 1 5 1 4 - - - - 1 5 1 4 POLYPODIACEA 2 2 0 0 8 9 - - 1 1 - - PORTULACACEAE 0 0 1 1 1 2 - - - - 1 1 PRIMULACEAE 1 1 1 1 - - 1 1 - - 1 1 RANUNCULACEAE 5 5 0 2 2 10 - 1 1 3 - 1 RHAMNACEAE 0 0 1 2 - - - - - - 1 2 ROSACEAE 9 9 0 8 3 14 - 4 - 2 - 6 RUBIACEAE 2 2 0 0 2 8 - 1 1 2 - - SALICACEAE 2 7 0 5 - 3 - - - 2 - 4 SANTALACEAE 0 0 0 0 1 1 - - - - - - SAURURACEAE 0 0 0 0 1 1 - - - - - - SAXIFRAGACEAE 1 2 1 2 4 4 - - - 1 1 2 SCROPHULARIAC 3 3 2 5 5 6 1 2 1 2 1 3 SELAGINELLACEAE 0 0 0 0 1 1 - - - - - - SOLANACEAE 2 2 1 3 - - - - 1 1 1 2 TAXACEAE 0 0 0 0 1 1 - - - - - - THYMELAEACEAE 0 0 0 0 1 1 1 1 - - - - TILIACEAE 1 1 0 1 - - - - - - - 1 TYPHACEAE 1 2 0 0 - - - - 1 2 - - ULMACEAE 2 3 0 0 - - - - 1 1 - - UMBELLIFERAE 3 2 1 2 6 9 1 1 1 1 - 2 URTICACEAE 1 1 0 0 1 1 - - - - - - VERBENACEAE 1 2 0 0 - - - - - 1 - - VIOLACEAE 1 2 0 1 1 7 - - - 1 - 1 VITACEAE 2 4 0 1 - - - 1 - 1 - - Composition of the flora has changed through time, and will continue to do so. Natural populations are altered by the blowdown of large trees, which occasion provides space and sun for a certain time for herbaceous species and for young trees and shrubs to become established until the space is again filled and shaded by a tree, and the herbs are forced out. There is some evidence that this was a frequent occurrence on Goat Island before European settlement. "... It seems likely that there was a time, probably not long ago, when other species of plants, of great beauty, were common upon the island, but which are not now to be found there. It is hardly possible that several orchidaceous plants and our three native lilies did not once embellish its woods and grassy places. Within a little while the Harebell (Campanula rotundifolia) is fast going. This is undoubtedly due to careless flower-gatherers, who have plucked and pulled without stint or reason. The same fate awaits the Sanguinaria [Bloodroot, which persists to this day], the Diclytras [= Dicentras, which have also survived] and the Trilliums [also persisting into 1988] ..." (Day, 1888). Native peoples, the "Seneca, Tuscarora and Tonawanda Indians sold wildflowers" before Goat Island became the Niagara Reservation (The Promontory Partnership, 1981), and may to some extent have been responsible for the loss of certain species of flowers, such as Day mentioned. However, it is more likely the native peoples sold species hardy enough to become souvenirs, such as autumn sprigs of the brilliant and aromatic Climbing Bittersweet (Celastrus scandens) once sold to tourists along the Niagara River gorge. Species with desirable root-systems could have been erradicated as they became over-harvested, such as Ginseng (Panax quinquefolia), and Burning Bush (Euonymus atropurpureus) (see the species catalogue and Zenkert, 1934). George Clinton noted in his diary two instances when acquaintances asked him to locate species of wild plants desirable for medicinal reasons - one involving Common Gromwell (Lithospermum officinale) and sought for on Goat Island (populations of this introduced plant are still vigorous on the island and throughout the Niagara Gorge). Day (1888) reported 285 native species on Goat Island, and 50 alien. Consultation with other records before 1940, which should account for all published reports of taxa observed there, has brought the number of species to 313 native, 75 alien. Since 1982 or so, native species discovered as present on Goat Island have shrunk to a total of 172 species, and the alien species count has increased to 155. Around 24 percent of the native flora has completely disappeared, and the flora of alien species has increased by 32 percent. It must not be assumed from the species catalogue that if a species is mentioned a viable population exists. In many cases, observation has revealed only one or two individuals on the verge of extirpation from the Goat Island complex, such as False Lily-of-the-Valley (Maianthemum canadensis), of which two depauperate individuals were seen at the edge of a path and which could be extirpated by one or two episodes of trampling, populations of Jack-in-the-Pulpit (Arisaema triphyllum) - two varieties of which were reported by Day (1888) as common - are represented by a few individuals, one small clump of Ramp (Allium tricoccum), also once abundant in 1888 in the central forest, and a population of American Germander (Teucrium canadense) on the Second Sister so small it escaped notice and is only included here by the assurance of another botanist (Alfred Schotz, pers. comm.). Other reports of species in the present catalogue do not suggest presence of reproducing individuals, and this may be the case with certain forest species, such as Beech (Fagus grandifolia), reduced to five or so individuals although once abundant, and Black Cherry (Prunus serotina). Many of these populations are so small or below the threshold by which they will produce offspring that a single act of man or nature could eradicate them from the Reservation altogether. This is also true in other areas in the flora of the the Niagara River Gorge. Considered on the generic level, the representation of native genera have been extirpated by 59 percent. Alien genera have increased by 52 percent. Alteration of the central woods accounts for the heavy loss (six genera, seven species) of members of the Lily family (Liliaceae), which constitute most of the spring ephemerals blooming in the woods in spring before the leaves develop on the trees. Woodland violets (Violaceae) also suffered both in their reputed abundance (Day, 1901) and in the high species loss (seven species out of eight). The fern family (Polypodiaceae) has been completely eliminated from Goat Island proper (eight genera, nine species), and a few representatives only exist today on the Second Sister and at the base of Goat Island. In the Daisy family (Compositae), there has been heavy loss in the once richly diverse native genus Aster where eight out of twelve species, most of them well represented elsewhere in the Niagara gorge and associated with woods and woods edges, have been extirpated. Half of the equally diverse Goldenrod species (Solidago) have been lost (five species). Many of the native species reported from the nineteenth century in the Daisy family that have disappeared on Goat Island probably also grew in the open prairie or meadow on the east end that was in secondary growth at that time, and which was converted to lawn early in the present century. These species are representative of the largest family of flowering plants in most parts of the temperate zone (Gleason, 1952). Certain groups, such as Goldenrods (Solidago sp.), are "native chiefly to North America, a few species extending into South America, and one or several into Eurasia; reaching its greatest complexity in eastern U.S." (Gleason, 1952). As for the genus Aster, "in the strict sense [it] reaches its greatest complexity in eastern U.S., but some of the segregates are more highly developed elsewhere" (Gleason, 1952). Most people native to northeastern North America are surprised when visiting foreign lands not to find any of their familiar Goldenrods and Asters, even when only visiting south of the United States in subtropical to tropical Mexico when traveling in autumn - the season when species of these two genera bloom. Visitors to the Goat Island complex whose homelands are in foreign lands would probably be fascinated by the autumn flora of the Reservation and in the Niagara River gorge. A booklet giving some key to the identification of species in these genera for foreign visitors would be valuable. These taxa are usually considered as weedy growth, which they are, favoring young areas of relatively recent disturbance. However, they are native, opportunistic taxa and very representative of the special flora that evolved in northeastern North America, and nowhere else in the world. Several families have become eliminated due to loss of habitat. Depletion of the once abundant Beech forest component accounts for the loss of Beechdrops (Epifagus virginiana, Orobanchaceae), which is parasitic on beech (Fagus grandifolia). The sole native member of the Aristolochiaceae, Wild Ginger (Asarum canadense), was probably lost by disturbance of its woods habitat. The Heath, or Blueberry, family (Ericaceae) has been eliminated with the disappearance of four genera and species. The shrubby blueberry (Vaccinium vacillans) probably grew on the crest, or high bank on the west end where it was dry and relatively open. The other three species were probably lost by disruption of the central woods. The Phlox family (Polemoniaceae), with its two native genera and species has been lost as has the Santalaceae, with one species. Loss of the wet, alluvial area by The Spring probably accounts for the loss of families with few members: False Mermaid family (Limnanthaceae), Lizard's-tail family (Saururaceae), and Mezereum family (Thymelaeaceae). Statistics for alien members of the Mint family (Labiatae) probably reflect nineteenth century interest in members of the family used for horticulture, for medicine and flavoring, especially alien members of the genus Mentha commonly known as Peppermint (M. piperita) and Spearmint (M. spicata). Some of these species were probably planted in the gardens of early settlers not for their attractiveness, but as a domestic medicinal crop. Bugle-weed (Ajuga reptans) was used for ailments such as jaundice, rheumatism, bleeding of the lungs, a "safe and mild narcotic" (Uphof, 1969) plant. Catnip (Nepeta cataria) had medicinal uses in addition to that of teasing cats. Motherwort (Leonurus cardiaca) is so-named because of its use in uterine disorders (Uphof, 1968). All of these alien species were reported as weeds growing on Goat Island in the nineteenth century - the largest representation, with seven genera and seven species, of early alien taxa of any of the families after the Compositae established by 1940. The Bean family (Fabaceae, or Leguminosae of some texts) has lost all of its native members (four genera, seven species), and not a single one of its alien ones, to which three genera and five species have been added since 1940. Many of its members are associated closely with lawns (Trifolium or the Clovers, Lotus corniculatus, or Bird's Foot Trefoil), Black Locust (Robinia pseudacacia) has been used horticulturally on the island margins, and Crown Vetch (Coronilla varia) to restore disturbed soils. Six native members of the Sedge Family (Cyperaceae) were probably lost when their habitats were eliminated on the east end of Goat Island (when this was covered with soil) and on dolomite flats areas, such as what is now Terrapin Point and the south side of the island in general. The Cattail family with its two species (Typhaceae) presently represented on the Three Sisters has been eliminated from Goat Island perhaps by the same process. Again, native conifers such as Ground Hemlock (Taxus canadensis, Taxaceae), Low Juniper (Juniperus communis) and Arbor Vitae (Thuja occidentalis, both in the Cupressaceae), all disappeared from the island, as well as nearly or all natural populations and mature individuals of other native conifers such as the White Pine (Pinus strobus) and Eastern Hemlock (Tsuga canadensis - both Pinaceae). Young planted colonies of the latter two species, however, appear to be thriving, and natural populations of Arbor Vitae occur frequently throughout the forest of the Niagara River gorge. There is a relatively high number of horticultural conifers that have been planted on Goat Island at various times for a century, and a large number of recent plantings. One striking alteration in the flora is the presence today of nine species of the Smartweed or Buckwheat Family (Polygonaceae), and probably indicates loss of woodland habitat. Although numerous species were reported by Day (1888) from mostly "waste areas on the mainland," there are no reports for members of this family anywhere in the Goat Island complex before 1940. Today there are nine species in two genera - weedy introductions and native species of disturbed or open habitats. A suite of species associated with wet soil has been lost, probably with loss of the old wet area depicted on the 1883 Evershed map of the Niagara Reservation on the island's north shore: False Mermaid (Floerkea proserpinacoides), Green Dragon (Arisaema dracontium), Leatherwood (Dirca palustris), Lizard's Tail (Saururus cernuus), Skunk Cabbage (Symplocarpus foetidus), Pale Touch-me-not (Impatiens pallida), Poison Sumach (Rhus vernix), and most of these probably vanished because they grew by the heavily altered Spring area, presently dominated by old plantations of horticultural species: Buckthorn (Rhamnus cathartica), Lilac (Syringa vulgaris), Norway Maple (Acer platanoides), Wayfaring Tree (Viburnum lantana). The island is always available for the establishment of new species. Although not researched for the present study, there is little doubt that the islands about the cataracts supported periodic influxes of migrating birds, especially water-fowl, several species of which even nested on the islands, such as Common Tern (Sterna hirundo), Herring Gull (Larus argentatus), and Ring-billed Gull (Larus delawarensis) (Andrle & Carroll, 1988). Some of these birds are associated with the coastline of the Great Lakes waterway; some of the diaspores of river and lake-margin plant species within the Great Lakes may be assumed to have reached the islands attached to these birds. This would be especially true of species entering the system downstream and found to migrate upstream, such as Flowering Rush (Butomus umbellatus). Seeds float downstream from the shoreline of the upper Niagara River, such as those of the Giant Hogweed (Heracleum mantegazzeanum) from stations at Beaver Island State Park, and perhaps Purple Loosestrife (Lythrum salicaria). It was easy to see bits of aquatic vegetation washed down from upstream habitats, such as Eel-grass (Vallisneria americana) and Water-weed (Anacharis canadensis) and bits of Myriophyllum and Potamogeton. It is probable that quite a bit of the introduced flora of the Goat Island complex came in with "garden soil," and other soils associated with the grading and upkeep of the lawns. Some of these species are ephemeral, found nowhere else than at the bases of recently planted trees and unlikely to spread or come up another year if for no other reason than that they will be mown or cleared away before they can become established. The weed flora, that is, alien species introduced in a variety of ways, most intensively through horticultural maintenance activities on Goat Island, have increased dramatically. They persist in the Goat Island environment due to the high percentage of artificial, open habitats such as lawns. The ecotonal areas bordering woods and thicket areas, garden-lawn boundaries and sidewalk cracks and joints between sidewalk and masonry - where soil accumulates and cracks exist where root systems can reach through to soil -presently abound on the Island and are maintained. As long as they are maintained, alien species will persist. The Daisy (Compositae) and Grass families (Gramineae) have proliferated mainly because large numbers of species-members, both native and alien, are opportunistic, taking advantage of any kind of disturbance in the environment to establish themselves. Native members of the Daisy and Grass family are characteristic of meadows, pastures and other open areas. Eastern North America is the center of dispersal for certain genera in the Daisy family, hence the large number of species in certain genera. Both of these families were well represented before 1940 and are presently the largest families on the island. Still, great losses have been sustained in the representation of native species in these families: over half, or fifty percent of native members of the daisy family (27 species) have become extirpated since 1940. Eighty-four percent of the native species in the Grass family have disappeared (11 species), whereas the alien species have increased by 260 percent (accounting for the loss of one alien species since 1940). Once alien species had established themselves, they tended to persist through time, indicating that whatever the changes were in the Goat Island environment, they favored alien, opportunistic species, and not native species associated with climax plant communities (spring ephemerals, ferns, violets, woodland species generally). Several native families and genera have lost their native members, but retained alien ones, including the Harebell family (Campanulaceae), Plantain family (Plantaginaceae); Cinquefoil (Potentilla), Columbine (Aquilegia), Thorn (Crataegus) Introduced families include an alien member of the the Loosestrife family (Lythraceae) by the introduction of Purple Loosestrife (Lythrum salicaria) and the Flowering Rush family (Butomaceae) by the establishment of Flowering Rush (Butomus umbellatus).
TOTAL REPORTS: Families: 98 Genera: 304 Species: 555 Native Genera: 221 Alien Genera: 83 Native Species: 374 Alien Species: 179 Historic records to 1940: Native Genera: 198 Alien Genera: 39 Native Species: 313 Alien Species: 75 TOTAL: 388 By around 1940 the total flora over time of Goat Island amounted to around 388 species of which approximately twenty percent were alien species and eighty percent were native. Day himself reported the loss of several species from Goat Island by 1888, although some of these he only conjectured existed there at one time, and may never have actually occurred there. Most notably some of the species reported by Douglas were not subsequently reported by botanists, and his reports seem to indicate the loss of a small boggy area during the period of private ownership. As noted above, since the area called the Spring was accessible to the public as one of the only sources of refreshment to early visitors to Goat Island, and since the course of Douglas' description seems to indicate that he visited a boggy area on the island's north side, where the bridge and spring were, before visiting the south side, it is likely he was describing conditions at the Spring. He also noted the wet habitat was in transition - drying out. Perhaps six of his species may be said to have disappeared by Day's time. The numbers of extinctions probably would not appreciably alter the percentages. Present records in the 1980's: Native Genera: 126 Alien Genera: 73 Native Species: 172 Alien Species: 155 TOTAL: 327 In the existing flora of around 327 species, 47 percent are alien species and 53 percent are native. Of the accumulated reports up to 1940, sixty-one species could not be presently accounted for, or a 16 percent loss in the diversity of the total 1940 flora, including both alien and native representations. Note that the diversity referred to does not indicate loss of native taxa and replacement by alien species associated with destruction of habitat, which has been ongoing throughout this century. Of the 313 native species reported for Goat Island by 1940, only 172 could be accounted for in this decade, representing a loss of fifty-five percent of the historic native flora, most of which has occurred in this century, or since state ownership of the Goat Island complex (the Niagara Reservation). The number of exotic species, mainly due to manipulation of the native ecosystem on Goat Island, has increased by 106 percent. Change through time: Extirpated: Native Genera: 93 Alien Genera: 12 Native Species: 202 Alien Species: 23 Introductions and New Reports: Native Genera: 23 Alien Genera: 44 Native Species: 62 Alien Species: 104
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