Skunk cabbage on an urbanising planet

To our knowledge, ours is the first urban-ecology study of eastern skunk cabbages (which are weird & wonderful, but whose ecology seems poorly known). Working at sites in and around New York City (NYC), we are asking five questions.

  1. Does urbanisation affect the distribution of eastern skunk cabbages? We know these plants love mucky areas in forests. Well, urban soils are often warmer and drier than non-urban soils and urban forests can be unlike natural forests in many other ways. We are using community-science data, e.g., iNaturalist, to document where they grow on an urban gradient.
  2. Is urbanisation associated with shifting phenology? We know that the urban heat island effect (UHI; most cities are warmer than outlying areas) and global warming are hastening flowering and fruiting in many species and locales. We are involving community scientists in monitoring plants in our sites to answer this question.
  3. Does urbanisation alter thermogenesis? The UHI could reduce the need to perform this costly behaviour, and this could have evolutionary implications. We are monitoring the temperature inside the spathes of focal plants and at ground level to see how far above ambient skunk cabbages raise their body temperature. We are also using quantitative PCR to measure the activity of the AOX gene (which is largely responsible for this behaviour) and will try to sequence it to ask if it has changed with urbanisation (among sites) and time (comparing with herbarium samples).
  4. Does the pollinator assemblage shift with urbanisation? Research has shown some urban-related changes in which species pollinate various plants. We are collecting environmental DNA (eDNA) from female and male spadices to identify the animals that touched them and are putative pollinators, as opposed to just hanging out in warm cozy spathes, which brings me to…
  5. Who lives in a spathe? During fieldwork, we saw unlikely pollinators, such as spiders and slugs, inside skunk-cabbage spathes (What is a spathe? Learn more here). Presumably, a spathe hosts a community of animals, bacteria, fungi and protists that use it as habitat and/or prey on it, besides its own microbiome. By treating each spathe as a habitat island, we are testing two ecological theories / ideas. If the Theory of Island Biogeography holds in this system, smaller and more isolated spathes should have fewer species compared to larger and more connected ones. And if the urban biotic-homogenisation hypothesis holds, then urbanisation should lead to a breakdown of the usual distance-dissimilarity relationship (whereby the farther apart two communities are, the fewer species they share). We are collecting eDNA from spathes and recording their sizes and dispersion patterns to test both theories at once.

Funding

This project is currently funded by the CUNY Interdisciplinary Research Grant, with Prof Alicia Meléndez as a co-investigator, and receives vital infrastructural and intellectual support from Profs John Dennehy and Timothy Short.