non-native invasive animals

NJ Invasive Species Conference

Click image above to download pdf version of conference agenda.

This is a wonderful opportunity to learn about non-native invasive species in New Jersey.  Experts will talk about the newest emerging threats, best management practices, and the latest biocontrol initiatives.  Roundtable discussion in the afternoon are geared toward digging deeper into these topics.

To register, click here.  

Hope to see you there!


Several folks have asked me in the past for a comprehensive guide to non-native invasive insects and diseases that affect trees.  Tom D. just sent along this link to a nice report by the National Park Service (NPS).

I took a quick look at it and for my purposes the dichotomous key in the beginning and Appendix C at the end provide a somewhat comprehensive list of forest pests and will be most useful.  Note that some of these pests are native and not considered “important” forest pests.  As with anything dealing with forest stewardship,  it is best to be very cautious about controlling certain pest outbreaks because they form an important part in forest ecology and forest stand dynamics.

However, as we all know, there are emerging threats to our forests that we should take very seriously.  There is a lot in this report about NPS rapid response procedures for these emerging threats that probably isn’t applicable to most of the lands we work on, but don’t forget we have the Central Jersey Invasive Species Strike team that can help fill the rapid response need and provide technical assistance in Central New Jersey.  It is too bad the NJ DEP doesn’t have the resources they should to address these types of emerging problems. And that the Governor eliminated the invasive species council. But that is another story ……

Let me know what you think after you have a read.

Here is the email from the National Park Service:

Damage to forest ecosystems from exotic invasive insect pests and pathogens has been increasing tremendously in the past decades, causing dramatic changes to forest ecosystems throughout the eastern United States.
Responding to requests from National Park Service (NPS) staff in the field for guidance on specific steps to manage a wide range of forest pests, the document, Rapid Response to Insect, Disease & Abiotic Impacts: Procedures to Protect Forest Integrity in Units of the National Park System within Eastern Forest, has been completed by staff from the Northeast, National Capital, Midwest and Southeast Regional Offices of the National Park Service. This is an electronic document, initially drafted by natural resource specialists in the Northeast Region. The document has been broadened to address concerns of all eastern regions, and is signed by the four Regional Directors of the eastern Regions of the National Park Service. The most recent revisions clarified the NPS guidelines to protect cultural resources, in addition to natural resources, when implementing the recommended procedures.

Although this is a document written by NPS natural resource specialists for NPS use, it can also be useful to state and local resource management agencies, contractors, and the general public. NPS has posted the document on the following public internet site:

A friend just forwarded me an interesting report from the Environmental Law Institute called Status and Trends in State Invasive Species Policy, 2002-2009. I haven’t read through the entire thing yet, but it is good to see how New Jersey compares to ten other states that have invasive species councils. I am somewhat comforted by the fact that NJ has an invasive species council and a comprehensive invasive species management plan.   However, the report points out that:

New Jersey has made no significant changes
to its laws and regulations related to invasive
species in recent years.

In the absence of state level laws, regulations, and resources, non-profit conservation organizations and particularly the Central Jersey Invasive Species Strike Team (CJISST) have begun to do a great job carrying out some of the recommendations of the comprehensive invasive species management plan, particularly as it relates to new, emerging invasive species.  It is clear, however, that in order to really get a handle on this problem we will need state laws and regulations as well as resources that only state government could provide.

I’d love to hear your comments about the report after you get a chance to read it.

It is great to see NJ Fish and Wildlife taking the threat of feral hogs so seriously.  

“They are one of the biggest threats to our environment because of the damage they do,” said Len Wolgast, a member of the state Fish and Game Council and former wildlife biology professor at Rutgers University.

Click here for a link to the article.  If that link doesn’t work, click here.

USGS Topographic Map Delaware Water Gap NRA

USGS Topographic Map Delaware Water Gap NRA



2007 Aerial Photograph Delaware Water Gap NRA

2007 Aerial Photograph Delaware Water Gap NRA

Since reading William Cronon’s classic “Changes in the Land” about 15 years ago, I have been fascinated by land-use change.  In fact, that is why I went to school to become a forester.  Forestry takes a scientific approach to land-use change.  My forestry education taught me how humans impacted and created land-use change (for better or worse).

The science of forestry focuses on past land-use disturbance, whether it be from logging, fire, tornado, flooding, or other event, to predict what the land will look like in the future.   It provides techniques to mimic these disturbance patterns and predicts subsquent plant species, habitat composition, and ecological function.  

Unfortunately, much of the land-use disturbance we face in New Jersey is novel and does not fit traditional forestry models. For example, the relatively new occurrence of overabundant white-tailed deer and non-native invasive plants absolutely affect how or even whether a forest re-grows after a disturbance.  

Although these two (1, 2) recent NY Times blog posts focus mostly on reinventing the built suburb using “New Urbanism” and other innovative planning concepts, they contain a thread of this novel land-use change idea; the suburb melting back into the wild.  

The topographic map and 2007 aerial above show what was likely going to be a lake community subdivision in what is now the Delaware Water Gap National Recreation Area (NRA).  I assume this abandoned subdivision was acquired by the Department of Interior when they were planning for the Tocks Island Dam project and creating Delaware Water Gap NRA.   Comparing historic topographic maps to current aerial photographs shows that there are likely several of these abandoned subdivisions in far northwestern New Jersey.

I am curious what half-built subdivisions would look like in the future if they were truly abandoned.  It probably wouldn’t be as bleak as the comments to the NY Times blog, and certainly wouldn’t be as widespread in New Jersey as it is in other places that were hit harder by the sub-prime mortgage mess.  However, it is fun thinking about post-suburban ecology.  What tree species would be present?  Would there be more native plants and animals or would non-native invasive plants and animals be dominant? 

Anyone want to ground truth a few old subdivisions in the Delaware Water Gap?

Feral hog


Here is an interesting policy from the NJ Division of Fish and Wildlife and an article from the AC Press on eradicating wild hogs in southern NJ.   It looks like the Division is not interested in New Jersey becoming like Texas or several other states, where they are a huge problem.  

I wonder why they only implemented this policy in Zone 25.  I have heard several stories about feral hogs in Northwestern NJ as well.   Regardless, it is great to see the Division taking such a strong stance on an invasive non-native species.  They should be commended.