The Tropical Dry Forests of Hawaii: 2013

Introduction

Dry Tropical Forest of Hawaii on the island of Oahu.

Tropical dry forests occur near the equator, and have a distinct dry and rainy season. They are controlled by the ITCZ and have many diverse plants such as short canopies, deciduous trees and unlike tropical rain forests, they have few epiphytes.Tropical Dry Forests can be found in Southern Mexico, SE Africa, central India, Madagascar, New Caledonia, Central Brazil, the Caribbean, along the Coasts of Ecuador and Peru, and Hawaii. The world's most endangered forests occurs in biodiversity hotspots, mainly along the tropics. The Dry Tropical Forest of Hawaii is the world's most endangered forest. (3 and Lecture Notes)

Map of the study area

http://www.sscnet.ucla.edu/geog/tdfpacific/hawaii.html#Molokai
http://www.youtube.com/watch?v=_49R_J8Zpaw

Mariam Hovhannisyan

Historical State of the Ecosystem: Then & Now

One of the best preserved tropical dry forests occur in Oahu.
This forest consists mainly of native species and is very similar to what the
Polynesians saw when they first arrived to the Hawaiian islands.

http://www.youtube.com/watch?v=_49R_J8Zpaw

Hawaii contains one of the world's most degraded ecosystems. The cause of this can be dated back to 2000-800 years BP, when the first Polynesians arrived on the Hawaiian islands. The arrival of the Polynesians caused a drastic change in the environment on all of the Hawaiian islands. In order to provide a habitat for living, the Polynesians practiced slash-and-burn agriculture and burned most of the forests in the lowlands. The Polynesians cleared most of the lowlands to plant taro, the staple of their diet and they also lived off of fish from the sea. (10) They brought 24 different species of plants with them that were used for various needs.(4) The planting of non-native species to protect watersheds for agriculture by the Europeans also prompted a loss of native tree species in the lowlands. The use of agriculture and land mass for living degraded a lot of the lowlands and now native tropical forests in the lowlands on most islands have disappeared. Native tropical forests are now only in isolated areas on steep slopes. On most islands, there is an abundant amount of diversity of trees. With sediment cores we can know what the original state of the forest was and what it looked like. The pollen in the sediment can tell us what types of species of plants were present before the Polynesians first arrived. (3)

http://www.sscnet.ucla.edu/geog/tdfpacific/hawaii.html#top
http://www.hawaiianencyclopedia.com/first-polynesians-first-hawaii.asp

Mariam Hovhannisyan

Benefits

The protected tropical dry forests of Hawaii are mostly healthy and lively. The typical dry forests in Hawaii are used to sustain livestock and are able to plant new exotic grasses. These help the diversity of the land and help to prevent wipe-out of species through one disease. In the early ages of the tropical dry forests, Polynesians used the land for growing agriculture as well as animal grazing. After the Polynesians, the use of the land was continued throughout the ages and has made a big impact on the lands of the tropical dry forests. The biggest benefit for people in this ecosystem is being able to plant crops because of the good condition of the tropical dry forests where it receives less than 50 cm of rain annually. The aesthetic nature of the forests also benefit many tourists and native peoples as well. (10)

http://www.sscnet.ucla.edu/geog/tdfpacific/hawaii.html

Jessica Hsieh

Current Human Impacts

Current Human Impacts

The current human impact on the tropical dry forests of Hawaii are currently in a bad condition. The continuous use of land for agriculture and animal grazing have consistently deteriorated the tropical dry forests over time. Though the land was burned years ago for agriculture and animal grazing, but the impact is still shown today. The effects can be seen since the current land suffers and can no longer recover from the forest fires. At the moment, humans have been cutting down these tropical dry forests in order to build new structures and profit from
development.(7)

Future

The future for tropical dry forest of Hawaii is currently looking down. With the constant use of these lands for agriculture and land development, the tropical dry forests are being continuously cut down. With buildings being set over these lands, there is no room for these tropical dry forests to live and sustain life anymore. Currently, the number of tropical dry forests have been decreasing and it is becoming increasingly hard to preserve these natural forests. If the current human impact continues to grow, most of the tropical dry forests of Hawaii will diminish and cease to exist.(5)

http://biology.uprm.edu/facultad/publications/Jarrod_Thaxton_20040101_.pdf

http://www.eoearth.org/view/article/153263/

Bird Species

The tropical dry forests of Hawaii have been reduced to about 10% of it's original size. Currently, in Hawaii, there are various patched of the ecosystem, spread out throughout the island. Originally, there were plenty of tree species on the tropical dry forest, which served as a habitat to many endemic bird species. However, many tree species have gone extinct due to human impacts and thus also reducing the amount of bird species in the ecosystem. Today, many endemic avifauna have become extinct or are critically low numbered. Other reasons for the extinction and endangered status of many bird species is the introduction of invasive species and disease.(9)

Endangered Crested Honey Creeper
Endemic to Maui

http://tropicaldryforestsofhawaii-birds.weebly.com/species-bios.html

Daisy Gallegos

What can be done to improve human impact?

This picture shows the relationship human
impact has on the dry tropical forests now and in the future.

Some scientists have begun investigative research in Hawaiian Tropical Dry Forests for controlling alien species invasions and to reestablish native species. Currently, over 25% of the officially listed endangered plant species in the Hawaiian flora are from the dry forest ecosystem and therefore the ecosystem is at serious risk of losing much of its biodiversity in the future if humans continue to impact the environment and do nothing to reestablish native species. The preservation of dry forest is also important for both biological and cultural reasons, because native Hawaiians used many of the endangered species. Therefore, there are several things that can be done to reduce disturbances, both natural and human caused such as, fire management, alien species management, provide economic incentives, reintroduction of native species, management of fences.

http://biology.uprm.edu/facultad/publications/Jarrod_Thaxton_20040101_.pdf

Daisy Gallegos

Protected Areas

Kokee State Park in Hawaii
http://americancountryside.com/wp-content/gems/2010/08/kokeestatepark.jpg

The Volcano National Park of Hawaii
http://www.hawaiiluxurynews.com/HLN/wp-content/uploads/2013/10/volcano.jpg

Two of the best protected tropical dry forests in Hawaii are the Volcano National Park and Kokee State Park. The status of these parks are in good condition, because these areas are closely monitored and visitors are informed as to the importance of keeping these habitats protected by not damaging the surrounding area or littering. The Volcano National Park is currently in a good situation because of the National Park Service and the efforts that it makes to work with American Indian tribes and local governments. (7) While working with these various organizations, the National Park Service works to provide $1.2 billion dollars in preservation grants and create 27 National Heritage Areas to help educate visitors of the preservation status of the Volcano National Park. Many of these protected areas are scattered across the islands of Hawaii and most of the protected areas are in good condition. However, the amount of tropical dry forests in Hawaii are beginning to diminish quickly due to human impacts. Poor choices from the government regarding land planning is contributing to the deterioration of the tropical dry forests. Human impact with agriculture and animal grazing, are causing these dry forests to become endangered. Because of this, there have been small preservations made throughout the islands of Hawaii to help decrease the rate of damage that is put upon the tropical dry forests. A big protected area is the Volcano National Park in Hilo and the Kokee State Park in Kauai. Since there are many diverse species in these parks, it is essential to keep the preservation status of these parks as best as possible. (6)

http://biology.uprm.edu/facultad/publications/Jarrod_Thaxton_20040101_.pdf

Jessica Hsieh
Mariam Hovhannisyan

Future Prospects

The chart above depicts outplant total from the 2007 census by

species at the Kaupulehu Dry Forest Hawaii Preserve. The Numbers

in parentheses represent the percent survival. Those 12 species

represent more than 90% of the total of the species outplanted

at Kaupulehu between 1999 and 2006. (2)

Over 90% of the lowland Shrublands have been lost in Hawaii’s Tropical Dry Forest because of human development and invasion of nonnative vegetation. Currently, the ecosystem is in a critical state and very endangered. Things such as fire, weed invasion, and feral animals threaten the future of Hawaiian Tropical Dry Forest (3). If efforts to preserve and restore these engendered areas are not made, there is a significant risk of losing much of its biodiversity. If the spread of alien species on the ecoregion continues, it could have a devastating impact, leading to permanent, low diversity grassland. Transects are also put in forests to get an idea of the species of trees that remain and what can be done to protect them(11). Fences have also been put around the native tropical dry forests to keep out invasive plants and to protect them from human and animal impact, but fences can be expensive and difficult to maintain. (video) The future prospects for the Tropical Dry Forest of Hawaii does not seem very good and could have detrimental effects for its overall survival, if we don't do anything about it.

http://www.fs.fed.us/psw/publications/cordell/psw_2008_cordell001.pdf

http://wwf.panda.org/about_our_earth/ecoregions/hawaiis_dry_forests.cfm
https://www.youtube.com/watch?v=_49R_J8Zpaw

Daisy Gallegos

Commentary: Our opinions on what can be done to improve the dry tropical forests of Hawaii

Mariam: One of the most important aspects about Hawaii is its tourism. Many people visit Hawaii whether it is for a vacation or travel. The more educated the people are about the endangerment of these forests on all of the various islands, the more likely it is that preservation of them will be improved. Educating tourists about the importance of these forests and what they can do to help will increase their interests and improve better prospects for these forests in the future. If each tourist new a little something about the tropical dry forest of the island they are staying on and what they can do to help would definitely help the preservation and protection of these forests.

Jessica: There are many different ways that humans can help preserve these tropical dry forests of Hawaii. Instead of slash and burn techniques for crops in these forests, there can be more sustainable methods. While working with crops and agriculture, humans should be more mindful of the land and take better care of the forests and the soil by replenishing nutrients back into the forests. This will allow more potential for the tropical dry forests of Hawaii to grow and sustain life easier. Along with this, less buildings should be built on top of the tropical dry forests. Since the tropical dry forests of Hawaii contain many unique and endemic species in the world, it would harm the species variability if these tropical dry forests were being continuously cut down.

Daisy: Because tropical dry forests are among the most endangered ecosystems in the world, humans must take an active role in preserving what remains of them. The tropical dry forests of Hawaii are a prime example of much bio diversity loss and should serve as a warning that if we stand idly by and allow current human impact in these dry tropical forest area, they could potentially turn into permanent low diversity grasslands. If humans continued to make efforts at restoring and preserving the ecosystem, we could see an increase in biodiversity once again. One of the main things that impacts the tropical dry forest of Hawaii is the invasion of alien species which continue to spread fire promoting grasses. Humans could focus on controlling such species and prevent fires. Another very beneficial thing that can be done is re-establishing native species and thus restoring the ecosystem.

Fun Facts about Hawaii

Hibiscus is the native flower of
Hawaii.
http://produceonparade.com/wp-content/uploads/2013/07/4155786_orig.j

The Hawaiian language consists of only 13 letter
The native flower of Hawaii, the Hibiscus, is very close to extinction with only one population with four plants left.
The dry lowlands of Hawaii contains almost 100% exotic species
Koa from the island of Molokai was used by native Hawaiians to make surfboards. (3)
Hawaii is sometimes called the "Paradise of the Pacific" because of its spectacular beauty, abundant sunshine, expanses of lush green plants and gaily-covered flowers.
Feral pigs, which were introduced to Hawaii by Polynesians 1500, are an invasive species on the island and the tropical dry forest because they eat massive amounts of vegetation causing native plant extinction.
Tropical dry forest of Hawaii contains nearly one quarter of native Hawaiian plant species.

http://conservancy.umn.edu/bitstream/60237/1/8.3.TepGaines.pdf

http://www.unep-wcmc.org/medialibrary/2011/05/24/6376095e/US%20Hawaii.pdf

https://www.youtube.com/watch?v=_49R_J8Zpaw

Mariam Hovhannisyan

Daisy Gallegos

Works Cited

1) Cabin Et Al. "Preservation and Restoration of a Hawaiian Tropical Dry Forest through Ungulate Exclusion and Non-native Species Control." United Nations Environment Programme. N.p., n.d. Web. 25 Nov. 2013.

<http://www.unepwcmc.org/medialibrary/2011/05/24/6376095e/US%20Hawaii.pdf>.

2) Cordell Et Al. "Towards Restoration of Hawaiian Tropical Dry Forests: The Kaupulehu Outplanting Programme." US Forest Service, n.d. Web. 25 Nov. 2013. <http://www.fs.fed.us/psw/publications/cordell/psw_2008_cordell001.pdf>.

3) Gillespie, Thomas W. "The World's Most Endangered Forests." YouTube. YouTube, 16 Sept. 2010. Web. 25 Nov. 2013.

<http://www.youtube.com/watch?v=_49R_J8Zpaw>.

4) Hawaiian Encyclopedia. "First Polynesians, First Hawaiians."Hawaiian Encyclopedia : First Polynesians, First Hawaiians. N.p., n.d. Web. 25 Nov. 2013. <http://www.hawaiianencyclopedia.com/first-polynesians-first-hawaii.asp>

5) Hogan, Michael. "Hawaii Tropical Dry Forest's." The Encyclopedia of Earth. N.p., 21 May 2013. Web. 24 Nov. 2013.

<http://www.eoearth.org/view/article/153263/>.

6) National Park Service. "Volcanoes Are Monuments to Earth's Origin, Evidence That Its Primordial Forces Are Still at Work." National Parks Service. National Parks Service, 15 Nov. 2013. Web. 22 Nov. 2013.

<http://www.nps.gov/havo/naturescience/volcanoes-are-monuments.htm>

7) Society for Ecological Restoration. "Restoration of Tropical Dry Forests in Hawaii." N.p., n.d. Web. 25 Nov. 2013. <http://biology.uprm.edu/facultad/publications/Jarrod_Thaxton_20040101_.pdf>.

8) Tep Et Al. "Reversing the Impacts of Feral Pig on the Hawaiian Tropical Rainforest Ecosystem." Restoration and Reclamation Review. N.p., n.d. Web. 24 Nov. 2013. <http://conservancy.umn.edu/bitstream/60237/1/8.3.TepGaines.pdf>.

9) UCLA. "Species Bios - Tropical Dry Forests of Hawaii and Their Birds." Tropical Dry Forests of Hawaii and Their Birds. N.p., n.d. Web. 27 Nov. 2013. <http://tropicaldryforestsofhawaii-birds.weebly.com/species-bios.html>.

10) UCLA Undergraduate Research. "Tropical Dry Forests of the Pacific - Hawaii." Tropical Dry Forests of the Pacific - Hawaii. UCLA, n.d. Web. 24 Nov. 2013. <http://www.sscnet.ucla.edu/geog/tdfpacific/hawaii.html>.

11) WWF. "Hawaii's Dry Forests." WWF. N.p., n.d. Web. 25 Nov. 2013. <http://wwf.panda.org/about_our_earth/ecoregions/hawaiis_dry_forests.cfm>.