Strangler Figs Research Articles

Substrate water potential constraints on germination of the strangler fig Ficus aurea (Moraceae)

Palms are the most common support hosts for strangler fig (Ficus aurea) in the tropical dry forest. At Hummingbird Cay Tropical Field Station in the Bahamas, viable F. aurea seeds scattered on open soil germinate within 6 d in the laboratory at 27C in light or darkness. To test the hypothesis that water relations between seed and substrate can restrict the site of F. aurea establishment, fig seeds were imbibed in mannitol solutions with water potential (psi) from 0 MPa to -2.0 MPa. At psi > -1.0 MPa, germination ranges from 70 to 90%. Below -1.0 MPa, germination drops under 4%. Seedling growth rate slows linearly with decreasing psi, due to reduced cell enlargement in the radicle. Sensitivity of F. aurea seeds to psi stress is similar to that of mesophytic crops with "threshold'' psi of -1.2 to -1.5 MPa, below which germination and/or seedling growth stops. F. aurea shows no evidence of xerophytic adaptation in germination physiology. In the field, psi of humus in palm leaf bases does not drop below -1.0 to -1.1 MPa, while humus in terrestrial sites reaches psi F. aurea germination and seedling growth is met by humus in palm leaf bases, not by terrestrial sites. In dry forests, this restricts F. aurea establishment to the crown of palm trees.

Strangler fig‐host associations in roadside and deciduous forest sites, South India

Abstract. Understanding the regeneration niche of animal‐dispersed epiphytes is important in understanding forest community structure, maintenance of species richness in plant communities, animal movements and distributions, and in managing plant and animal communities for conservation. Strangler figs are particularly interesting for studying epiphyte‐host relations because they are hemiepiphytes, implying that strangler and host can potentially belong to the same species and either fuse together or strangle each other, and because all stranglers have many‐seeded, animal‐dispersed fruit, providing many opportunities for seed dispersal to other stranglers. A study was conducted at a roadside and at a forest site in Karnataka State, south India, to determine factors influencing host choice of strangler figs. Stranglers were found more frequently at the roadside site than at the forest site. At the roadside site, stranglers were found much more abundantly on Ficus hosts than on non‐Ficus hosts, whereas at the forest site, stranglers were found more abundantly on non‐Ficus hosts. Host tree species with animal‐dispersed fruit bore significantly more stranglers than those with mechanically dispersed fruit. More stranglers were found on hosts in large d.b.h. size classes (>80 cm d.b.h.) than on those in small d.b.h. classes. Prior studies of strangler‐host relations have never found stranglers growing on other stranglers. The results of this study suggest that stranglers are fully capable of regenerating on other stranglers, including conspecifics, but these regeneration events are not observed in forests because of relatively low strangler seed rain, due to lack of clumping of strangler hosts, and low insolation in these habitats.

Paternity analysis of the breeding structure of strangler fig populations: evidence for substantial long‐distance wasp dispersal

Abstract. The mutualistic interaction of figs with their species‐specific wasp pollinators and the role of figs as ‘keystone’ plant resources in tropical communities has received substantial attention from both plant and animal ecologists. Despite this focus on the reproductive biology of figs, the minute size of the wasps has effectively precluded our ability to monitor patterns of wasp dispersal and fig mating relationships in natural forest habitats. In this paper we use genetic markers and genealogy reconstruction techniques to examine the breeding structure of populations of four strangler fig species occurring in central Panama. The natural history of figs facilitates the genetic analysis of full‐sib progeny arrays from which the genotypes of successful pollen donors can be reconstructed precisely. Paternity reconstruction in the four study species reveals that individual flowering trees may routinely receive pollen from numerous donors despite characteristically low densities of co‐flowering individuals. These data indicate not only that breeding populations of these figs are larger than the minimum critical sizes predicted to be necessary to support populations of their species‐specific pollinators, but are more extensive in size and area than has been described for any plant species yet examined. Further, the fig wasps are shown to be efficient agents of long‐distance dispersal, routinely moving up to 10 km between flowering trees. In accord with the potential for substantial long‐distance gene flow and large effective population sizes, ten of eleven species of Panamanian figs assayed were found to maintain exceptionally high levels of genetic variation within their populations. Combined with other reports of occasional long‐distance dispersal, the results of this study suggest that fig wasps may be more effective at colonizing isolated fig populations than previously thought.

Water relations of epiphytic and terrestrially-rooted strangler figs in a Venezuelan palm savanna.

Water use patterns of two species of strangler fig, Ficus pertusa and F. trigonata, growing in a Venezuelan palm savanna were contrasted in terms of growth phase (epiphyte and tree) and season (dry and wet). The study was motivated by the question of how C3 hemiepiphytes accommodate the marked change in rooting environment associated with a life history of epiphytic establishment followed by substantial root development in the soil. During the dry season, stomatal opening in epiphytic plants occurred only during the early morning, maximum stomatal conductances were 5 to 10-fold lower, and midday leaf water potentials were 0.5-0.8 MPa higher (less negative) than in conspecific trees. Watering epiphytes of F. pertusa during the dry season led to stomatal conductances comparable to those exhibited by conspecific trees, but midday leaf water potentials were unchanged. During the rainy season, epiphytes had lower stomatal conductances than conspecific trees, but leaf water potentials were similar between the two growth phases. There were no differences in ∂13C between the two growth phases for leaves produced in either season. Substrate water availability differed between growth phases; tree roots extended down to the permanent water table, while roots of epiphytic plants were restricted to material accumulated behind the persistent leaf bases of their host palm tree, Copernicia tectorum. Epiphytic substrate moisture contents were variable during both seasons, indicating both the availability of some moisture during the dry season and the possibility of intermittent depletion during the rainy season. Epiphytic strangler figs appear to rely on a combination of strong stomatal control, maintenance of high leaf water potentials, and perhaps some degree of stem water storage to cope with the fluctuating water regime of the epiphytic environment.

Roost selection by the north Queensland long‐eared bat Nyctophilus bifax in littoral rainforest in the Iluka World Heritage Area, New South Wales

Abstract The aim of this study was to describe the roosts of Nyctophilus bifax in littoral rainforest in Iluka Nature Reserve on the north coast of New South Wales. Radio‐telemetry was used to track 17 bats in November 1988 (lactation season) and 11 in May 1989 (mating season) to 87 roosts in 49 trees within the littoral rainforest. The bats frequently changed roosts, which were clustered within a small area. During November, lactating females moved twins between diurnal roosts and some carried twins while foraging. Twins represented a load of up to 95% of their mother's bodyweight. Bats roosted communally in foliage and tree hollows, beneath peeling bark, among epiphytes, and between strangler figs and host trees. Hollows were used more frequently when bats were lactating, while the use of foliage roosts was greater during the mating season. Roosts were concentrated in four tree species, although a wide range of other tree species was used. Roost trees used in November were taller (17m) than those used in May (8. 2 m), and reflect selection of Syzygium leuhmannii and Acmena hemilampra, both trees of the forest interior. The converse applied for selection of Cupaniopsis anacardioides, a small tree of the littoral zone, in May. These results identify the need for conserving a diversity of roosts for this species of bat.

Comparative Phenology of Epiphytic and Tree-Phase Strangler Figs in a Venezuelan Palm Savanna

Epiphytic and tree-phase individuals of two hemiepiphytic figs (Ficus pertusa and F. trigonata) growing in a seasonally dry palm savanna in central Venezuela were compared on the bases of leaf longevity and temporal patterns of leaf production and loss. Epiphytic plants of both species produced new leaves more often and had a greater number of transitions from leaf-bearing to leafless than conspecific trees during the two-year observation period. Leaf production by epiphytic plants but not by trees of either species was positively correlated with rainfall received during the fortnight prior to phenological observation. Epiphytic plants of both species were leafless or nearly so during more of the year and had more separate episodes of becoming deciduous than conspecific trees. Periods of leaf loss generally coincided with dry periods but the negative correlation with rainfall during the previous fortnight was significant only for F. pertusa trees. Leaf life spans were shorter on epiphytic than on tree-phase figs. Pattems of leaf production and loss are interpreted to be responses to water deficits suffered by epiphytes, deficits that are at least partially overcome when plants becomes deeply rooted in the ground.

Temporal Patterns in Diet of Nestling White-Crowned Pigeons: Implications for Conservation of Frugivorous Columbids

The timing and production of crop milk are important to the reproductive tactics of granivorous columbids, but little is known about crop-milk production in frugivorous columbids. We examined the diet of nestling White-crowned Pigeons (Columba leucocephala) and the relative contributions of crop milk and fruit during different stages of nestling development. The diet was dominated by five species of plants: Metopium toxiferum (poisonwood), Guapira discolor (blolly), Ficus citrifolia (shortleaf fig), F. aurea (strangler fig), and Erithalis fruticosa (black torch). Fruit of F. aurea and F. citrifolia dominated the diet during May and June. Fruit of M. toxiferum, which began to ripen in early July, dominated the diet through September. Guapira discolor was found in the diet throughout the nesting season and, overall, ranked as the second-most-important food. Erithalis fruticosa was found in small amounts in samples collected throughout the season. Crop milk remained an important component of the diet throughout the nestling period. As nestlings grew, fruit was added to the diet. At ages 0 to 2 days, the diet was entirely crop milk. The proportion of the diet composed of fruit increased from 10% on day 3 to 65% at day 15. These data suggest that the reproductive tactics of frugivorous pigeons may differ from those of granivorous pigeons. We speculate that frugivorous columbids may continue to supplement the diet of nestlings and fledglings with crop milk. Although this behavior may enhance growth rates and survival of individual young, it also may lengthen the interclutch interval. These findings emphasize the conservation importance of protecting large feeding areas to maintain populations of threatened and endangered frugivorous pigeons.

Host relationships of Ficus burtt-davyi when growing as a strangler fig

The fig tree Ficus burtt - davyi Hutch. is a common strangler of other trees in the Alexandria Forest, South Africa. Unlike most strangler figs, there is rarely extensive fusion of the roots around the trunks of the host trees. This, together with the relatively small size of F . burtt - davyi , means that damage to the hosts is limited. Between-species differences are present in the likelihood that trees will support F . burtt - davyi . No stranglers were found on Erythrina caffra , nor was auto-strangulation of other F. burtt - davyi recorded. Laboratory trials suggest that the absence of stranglers from these species does not result from chemical inhibition of F . burtt - davyi seed germination.

Genetic Mosaics in Strangler Fig Trees: Implications for Tropical Conservation

Single trees of six species of strangler figs (Ficus spp., Moraceae) in Panama were found to be made up of multiple genotypes, presumably formed by the fusion of different individuals. The phenomenon is frequent enough that strangler fig populations will contain considerably more genetic variation than would be expected from the number of trees. How this cryptic variation affects populations depends on the flowering phonology of composite trees. If the genetically different portions of trees flower asynchronously, populations of pollinating wasps may be more resistant to low host population sizes than previously thought. If different portions flower synchronously, attempts to infer mating-system parameters from the parentage of fruit crops will be misleading. The fruiting of figs, which are considered a keystone species in tropical forests, is important for maintaining biodiversity but is also particularly susceptible to failure at small population sizes. It is therefore important to know both the number of trees and the number of genotypes in a population.

STRANGLER FIG ROOTING HABITS AND NUTRIENT RELATIONS IN THE LLANOS OF VENEZUELA

The strangler figs, Ficus pertusa and F. trigonata, are abundant in the seasonally flooded palm savanna (llanos intermedio) near Calabozo, Venezuela. The most common host tree for the hemiepiphytic figs is the palm Copernicia tectorum; nearly half of the palms support either an epiphytic or a ground‐rooted fig. During their epiphytic stage the figs are rooted behind the palms' marcescent leaf bases. Material trapped behind the leaf bases is higher in organic matter, nitrogen, magnesium, and potassium than soil from the ground near the palms. The suggestion that nutrient availability to epiphytes is high is supported by the observation that concentrations of several nutrients, including N, P, and K, are significantly higher in epiphytic leaves than in tree leaves. Figs retain access to the epiphytic medium by producing upwardly growing (apogeotropic) roots that remain attached in the host palm's crown long after the fig has become firmly rooted in the ground. Although upward growing roots are expected to be more important in nutrient than water uptake, there are no obvious differences in the xylem anatomy of upward and downward growing fig roots. Terrestrial roots of fig trees are generally infected with vesicular‐arbuscular mycorrhizae, but the epiphytic roots of the same individuals are not infected.

Strangler Fig Rooting Habits and Nutrient Relations in the Llanos of Venezuela

Strangler Fig Rooting Habits and Nutrient Relations in the Llanos of Venezuela

Temporary parasitism of Coriolus spp. by Lenzites betulina: A strategy for domain capture in wood decay fungi

Temporary parasitism by individual of the wood-decaying basidiomycete Lenzites betulina allows them to gain selective access to wood occupied by populations of pioneer basidiomycete colonisers in the genus Coriolus. Pseudotrametes gibbosa is similarly temporarily parasitic on species of Bjerkandera. This strategy facilitates possession by the parasites of a large mycelial domain, which in turn allows them to produce large sporophores with a high reproductive output. This behaviour strongly resembles that of strangler figs and temporary social parasitism in ants.

Temporary parasitism of Coriolus spp. by Lenzites betulina: A strategy for domain capture in wood decay fungi

Temporary parasitism by individual of the wood-decaying basidiomycete Lenzites betulina allows them to gain selective access to wood occupied by populations of pioneer basidiomycete colonisers in the genus Coriolus. Pseudotrametes gibbosa is similarly temporarily parasitic on species of Bjerkandera. This strategy facilitates possession by the parasites of a large mycelial domain, which in turn allows them to produce large sporophores with a high reproductive output. This behaviour strongly resembles that of strangler figs and temporary social parasitism in ants.

Fruiting and frugivores at a strangler fig in the tropical rain forest of Los Tuxtlas, Mexico

ABSTRACTDiurnal and nocturnal censuses were conducted on animal visitors at a single strangler Ficus aff. cotinifolia (H.B.K.) tree during the entire period of ripe fruit availability. Fruit fall to the ground was measured with fruit traps, and chemical analyses were conducted on the figs. Fourteen species of birds, four species of nonvolant mammals and two species of bats consumed the figs. Of the total number of ripe figs accounted for during the sampling period (N= 1.9 X 105), 42% fell to the ground, 45% were removed by mammals and 13% by birds. Frugivores such as the howling monkey Alouatta palliata, the cacomistle Bassariscus sumichrasti, the keel-billed toucan Ramphastos sulphuratus and fruit-eating bats removed the largest amounts of figs from the tree and deposited seeds of 13 plant species other than figs below the tree crown.

Earle, Olive L. The strangler fig and other strange plants. New York 10016 (425 Park Avenue South): William Morrow and Company, Inc., 1967. 64 P. $2.95

Science EducationVolume 52, Issue 1 p. 95-95 Book Review Earle, Olive L. The strangler fig and other strange plants. New York 10016 (425 Park Avenue South): William Morrow and Company, Inc., 1967. 64 P. $2.95 First published: February 1968 https://doi.org/10.1002/sce.37305201122AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume52, Issue1February 1968Pages 95-95 RelatedInformation

Field Observations on the Habits of Aedes Taeniorhynchus

The east or Atlantic coast of Florida is paralleled by a chain of narrow islands which are often referred to as the Beach. In the vicinity of Fort Pierce, the lagoon separating this offshore bar from the mainland is called Indian River (Fig. 1) . The outer or ocean beach is very straight and is backed by dunes behind which a number of plant associations parallel the coast. These increase in height as they succeed one another westward, from grass and weeds, through palmetto scrub, to the coastal hammock, a dense forest dominated by oaks and Sabal palms (for details, see Kurz 1942, and Davis 1943). The Indian River shore is a confusion of islands, peninsulas, coves, and sounds, more or less inundated by tide and covered with mangrove and salt marshes. These are the typical breeding areas for salt-marsh mosquitoes, and a considerable amount of control ditching was done here in the past. In the Fort Pierce region, both of Florida’s salt-marsh Aedes occur, but during the observation period under discussion, Aedes taeniorhynchus (Wiedeman) predominated while Aedes sollicitans (Walker) was present in negligible numbers only. We made our studies on the property of Mr. P. McConville, some six kilometers (4 mi.) north of Fort Pierce on the offshore bar. Most of the observations were made along a narrow winding road traversing this property from highway AlA near the outer beach to the Indian River shore (Fig. 1). This road crosses a number of the typical plant associations. In the first hundred meters from the highway, it cuts across palmetto scrub with Serenoa, CoccoZobis, Lantana, and other shrubs. It then curves WNW and passes through a hammock zone with a denser vegetation of oaks and palms. In this stretch the road ,crosses three old ditches which have become series of pools. Some of these pools hold water fairly continuously, but most of them, as well as the road tracks which bisect them, are flooded for short periods only after rains. These ditches are lined with mangrove and with Batis maritiuuut, Borrichia fru tescens, and Salicornia sp. Beyond the ditches, the vegetation along the road becomes more open, with many isolated shrubs separated by grass and such weeds as Chamecrista. Several kinds of vines mantle this vegetation. The road then turns SSW and in a number of short turns passes through an old orchard, mostly of mango and guava, with several rare imported trees and bushes. This orchard has grown wild for ten years and is now a dense scrub. The road ends at the Meadow (Fig. 2)) a triangular open area of about half an hectare (1 acre). It is mostly covered with a Paspalum turf and patches of young (l-2 m. high) mangrove along the several small pools and ditches. The meadow is bordered with high Guinea grass, and in the immediate surroundings are several unusual large palms, oaks, and strangler figs. Groundsel-bush (Baccharis halinzifolia), a 2-3 m. high shrub belonging to the composite family, is found at many places along the road and is especially common on the edge of the meadow.