Biodiversity patterns and ecological processes in Neotropical dry forest: The need to connect research and management for long-term conservation.

Abstract

Neotropical dry forests are among the most diverse and threatened ecosystems worldwide. The extent and knowledge of Neotropical dry forests are quite heterogeneous with forests located in the Ecuadorian province especially diverse, threatened and poorly studied. In this work, we review patterns and conservation status of biodiversity, ecosystem processes and human perception of tropical dry forest of the Ecuadorian province. We found that patterns of biodiversity, endemism and conservation status are generally poorly studied. Overall, these forests provide habitat for at least 900 species including trees, birds, mammals, amphibians and reptiles. On average 18% of these species (range 6–25%) are endemic to the region and 25% (3–50%) are recognized as threatened. Little is known about groups such as invertebrates, fish, fungi, or herbaceous plants, and as well as about processes generating and maintaining critical ecosystem functions. Available literature points out the importance of positive ecological interactions such us plant–frugivore and plant–plant facilitation interactions in maintaining the regeneration dynamics of these forests. Faced by the formative state of knowledge about basic biodiversity patterns and ecological functions, the implementation of ecosystem risk assessment under the IUCN criteria for the Red List of Ecosystems may offer constructive means to organize, integrate and advance existing knowledge and conservation priorities for dry forests of the Ecuadorian province. With examples of existing conflicts between people and protected areas, we emphasize the importance of consultation and involvement of local communities in the development of conservation measures including new protected areas. Lastly, we reflect on some encouraging examples where ecosystem goods and services provided by these forests may be used in a sustainable manner, contributing to local communities’ income and preserving biodiversity. In this regard, we highlight how the
interaction between research and innovation together with local management may lead to sustainable development and, thus, encourage these sectors to work together for the conservation of dry forests of the Ecuadorian province.

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Biodiversity patterns and ecological processes
in Neotropical dry forest: the need to connect
research and management for long-term
conservation
Gema Escribano-Avila, Laura Cervera, Leonardo Ordóñez-Delgado, Andrea
Jara-Guerrero, Luis Amador, Bruno Paladines, Joahana Briceño, Violeta
Parés-Jiménez, Diego J. Lizcano, David H. Duncan & Carlos Iván Espinosa
To cite this article: Gema Escribano-Avila, Laura Cervera, Leonardo Ordóñez-Delgado, Andrea
Jara-Guerrero, Luis Amador, Bruno Paladines, Joahana Briceño, Violeta Parés-Jiménez, Diego
J. Lizcano, David H. Duncan & Carlos Iván Espinosa (2017) Biodiversity patterns and ecological
processes in Neotropical dry forest: the need to connect research and management for long-term
conservation, Neotropical Biodiversity, 3:1, 107-116
To link to this article: http://dx.doi.org/10.1080/23766808.2017.1298495
© 2017 The Author(s). Published by Informa
UK Limited, trading as Taylor & Francis
Group
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Biodiversity patterns and ecological processes in Neotropical dry forest: the need to connect
research and management for long-term conservation
Gema Escribano-Avila
a
*, Laura Cervera
b
, Leonardo Ordóñez-Delgado
a
, Andrea Jara-Guerrero
a
,
Luis Amador
c,d
, Bruno Paladines
e
, Joahana Briceño
a
, Violeta Parés-Jiménez
b
, Diego J. Lizcano
b
,
David H. Duncan
a
and Carlos Iván Espinosa
a
a
Natural Science, Universidad Tecnica Particular de Loja, Loja, Ecuador;
b
Central Department of Research, Universidad Laica Eloy
Alfaro de Manabi, Manta, Ecuador;
c
Science Faculty, Universidad Austral de Chile, Valdivia, Chile;
d
Research Department,
Universidad Laica Vincente Rocafuerte de Guayaquil, Guayaquil, Ecuador;
e
Naturaleza y Cultura Internacional, Loja, Ecuador
(Received 26 April 2016; accepted 17 February 2017)
Neotropical dry forests are among the most diverse and threatened ecosystems worldwide. The extent and knowledge of
Neotropical dry forests are quite heterogeneous with forests located in the Ecuadorian province especially diverse, threat-
ened and poorly studied. In this work, we review patterns and conservation status of biodiversity, ecosystem processes
and human perception of tropical dry forest of the Ecuadorian province. We found that patterns of biodiversity, ende-
mism and conservation status are generally poorly studied. Overall, these forests provide habitat for at least 900 species
including trees, birds, mammals, amphibians and reptiles. On average 18% of these species (range 6–25%) are endemic
to the region and 25% (3–50%) are recognized as threatened. Little is known about groups such as invertebrates, fish,
fungi, or herbaceous plants, and as well as about processes generating and maintaining critical ecosystem functions.
Available literature points out the importance of positive ecological interactions such us plant–frugivore and plant–plant
facilitation interactions in maintaining the regeneration dynamics of these forests. Faced by the formative state of
knowledge about basic biodiversity patterns and ecological functions, the implementation of ecosystem risk assessment
under the IUCN criteria for the Red List of Ecosystems may offer constructive means to organize, integrate and advance
existing knowledge and conservation priorities for dry forests of the Ecuadorian province. With examples of existing
conflicts between people and protected areas, we emphasize the importance of consultation and involvement of local
communities in the development of conservation measures including new protected areas. Lastly, we reflect on some
encouraging examples where ecosystem goods and services provided by these forests may be used in a sustainable
manner, contributing to local communities’income and preserving biodiversity. In this regard, we highlight how the
interaction between research and innovation together with local management may lead to sustainable development and,
thus, encourage these sectors to work together for the conservation of dry forests of the Ecuadorian province.
Keywords: Tumbesian region; Equatorial Pacific region; IUCN ecosystem risk assessment; endemism; sustainable
development
Introduction
Tropical dry forests (TDFs), perhaps the most threatened
terrestrial biome in the tropics [1,2], sustain a high diver-
sity of plants and animals and ecological functions that
supply a multitude of ecosystem goods and services to
local human populations [3]. These forests encompass a
variety of form and composition across three continents
[4] and have long resisted the imposition of a clear
definition [3,5]. However, two simple characteristics
define TDFs globally: forests occurring in the tropics
(temperatures above 20º, complete absence of frosts) that
experience marked rainfall seasonality with several
months of drought (5–8 months) [6,7] generating a partic-
ular ecosystem structure and physiognomy that is shared
among TDFs [2,5]. For many of the same reasons, tropical
dry forests have typically coincided with areas of dense
human inhabitation and land conversion [2], which now
render this ecosystem extremely threatened [8,9].
Despite its more acute exposure to anthropogenic
threats, and great relevance for human settlements over
millennia, TDF remain poorly studied, especially in
comparison to their latitude neighbors’, tropical wet and
rainforests [3,8]. From 1945 to 2004, for each research
paper published in the Web of Science portal about tropi-
cal dry forests, six were published on tropical wet forests
[10]. In a more recent review (1997–2014), this ratio has
slightly increased to one research article on tropical dry
forests for each 4.5 in rainforest, but still only 10% of
the research work performed in the tropics is about dry
ecosystems (Cayuela et al. unpublished results) Within
those articles concerning dry forests from the Neotropical
region, one also finds a stark imbalance. Two countries,
México and Costa Rica have attracted ~70% of the sci-
entific research (Figure 1), while other areas in Central
and South America are virtually unknown. For example,
TDFs in Bolivia are the subject of less than 5% of
*Corresponding author. Email: gema.escribano.avila@gmail.com,gescribano@imedea.uib-csic.es
© 2017 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits
unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Neotropical Biodiversity, 2017
Vol. 3, No. 1, 107–116, http://dx.doi.org/10.1080/23766808.2017.1298495

research articles despite representing 25% of the overall
extension of Neotropical dry forests [10].
Around the border of Ecuador and Peru exists
another highly diverse and threatened area of tropical
dry forest, variously known as the Equatorial Pacific
Region, Tumbesian region, or Tumbes-Piura [11–15].
Despite the great importance of such forests in terms of
biodiversity and endemism [11,14], these have been lar-
gely neglected in the literature on Neotropical dry forests
[2,11]. According to the above-mentioned analysis, the
area is represented by only 3% of tropical dry forest
studies (Figure 1). Part of this area is the focus of our
review. According to the most recent update on Neotrop-
ical bioregionalization, the area target of this review has
been denominated the Ecuadorian province [16].
Hereafter, we will refer to the target area and ecosystem
of this study as tropical dry forest of the Ecuadorian Pro-
vince (EP-TDF).
The EP-TDF conforms one the ecological sub-units
of the Tumbes-Chocó-Magdalena hotspot [17]. It covers
a narrow strip of coastal hinterland delimited by the
Pacific Ocean and the lower slopes of the Andes, extend-
ing over a distance of ~900 km from southeast Ecuador
to northeast of Peru (Figure 2). The TDF-EP experiences
a profound influence of the cold and dry Humboldt cur-
rent and it is intermittently influenced by the warm and
wet El Niño current, both determining the strong season-
ality encountered in this area [18].
The extent of the EP-TDF has been vastly deforested
to the present day, where only about 30% is thought to
remain relatively undisturbed (25 and 5% in Ecuador
and Peru respectively) and only 10% of it is under some
kind of protective land designation. These historical
facts, together with the current rate of deforestation,
5–10% for the period 2000–2012, [9,19] suggest a bleak
future for TDF-EP, unless significant changes to land use
and development patterns actions are implemented. The
future wellbeing of the EP-TDF is tightly bound to the
livelihoods of the many people who live in and around
them. To satisfy the needs of people living in EP-TDF is
a necessary condition for the present and future conser-
vation of this ecosystem; this may be achieved only if
all stakeholders, people, managers and researches work
together.
The aim of this review is to identify gaps in knowl-
edge of biodiversity and ecosystem functioning of EP-
TDF. We also consider how the nearby human popula-
tions, historically the principal degrading agent of the
forests, currently perceive the forest and how they may
contribute to a more sustainable future. We think the
consideration of all this information together, may guide
future efforts to generate the necessary knowledge to
perform an ecosystem risk evaluation according to the
IUCN criteria for the Red List of Ecosystems. The topics
discussed herein resulted from a dynamic multidisci-
plinary workshop hosted by Universidad Técnica
Particular de Loja (Ecuador) in November 2015. The
workshop brought together researchers from various dis-
ciplines and conservationists, both concerned and enthu-
siastic about the future of the EP-TDF.
This review is articulated around several themes
dealing first with the interaction of people and forests.
EP-TDF has been occupied and utilized by various peo-
ples for millennia [3]. Now that only 30% of the former
extent of EP-TDF still remains, the management of these
interactions is more important than ever. Researchers
should seek to generate the necessary knowledge to help
overcome such challenges [20]. More information about
the biological diversity in EP-TDF should help identify
and develop management options for conservation and
sustainable use. We discuss key advances and gaps in
knowledge about biodiversity patterns and ecological
functions and processes, and also we tackle some
possible synergies between ecological research and local
management that may contribute to the long-term conser-
vation of the EP-TDF.
Figure 1. Number of studies published in the Web of Science in the period 1900–2015 (search performed on December 2015) using
the words ‘Tropical dry forest’and ‘country name*’in the title, keywords and abstract. Numbers above each bar represent the
percentage of studies in each country.
108 G. Escribano-Avila et al.

Figure 2. Location of dry forest of the Ecuadorian province in Peru and Ecuador, highlighting protected areas.
Neotropical Biodiversity 109

Tropical dry forest of the Ecuadorian province,
protected areas and people
Tropical dry forests of the Ecuadorian province are
found mainly along the coastal hinterland (Figure 2).
Therein, the gentle topography, ease of access, fertile
soils and moderate climate have favored the presence
and settlement of human populations for around five to
nine millennia [21]. The expansion of the human settle-
ments and activities such as natural resource extraction,
agriculture and extensive grazing have combined to ren-
der EP-TDF one of the most threatened ecosystems in
the world [2]. Activities involving deforestation in partic-
ular, have fragmented extant habitat directly impacting
species richness and biodiversity [22,23].
Official protection of remnant EP-TDF habitat has
progressed through a variety of regional, national and
internationally recognized reserves. In Peru, ~10% of
remnant dry forest (2337 km
2
) is protected by means of
six protected areas (Figure 2), most of them included in
the UNESCO Northwest Biosphere Reserve (NBR),
which covers an area of 231 km
2
. In Ecuador, dry forests
occupy more than 6000 km
2
[9]. Until 2014, only 2–4%
was protected in conservation reserves [9,24]; however,
this percentage recently rose to an estimated 8% of the
extant tropical dry forests, following the declaration of
Bosque Seco Biosphere Reserve (BSBR). The BSBR
declaration was facilitated by the efforts of various
municipal authorities to define zones within their juris-
diction critical for conservation and ecosystem connectiv-
ity. The Municipal Reserves that resulted from the
zoning process today largely comprise the core area of
the BSBR. The recognition of the conservation value
and objectives, and the legal status established by the
declaration were positive and necessary steps, and the
establishment of protected areas has contributed to slow
down deforestation rates. However, the designation of
protected areas does not in itself assure long-term biodi-
versity conservation (reviewed in [25]). The management
of protected areas in developing countries is often com-
plex because of poverty, population growth and the lack
of resources available for effectively protecting those
areas [25].
Machalilla National Park, the only Ecuadorian
national park that includes dry forests, exemplifies the
conflicting interests of local communities and national
park management objectives. The park was created in
1979 without much consultation with local communities.
Consequently, illegal activities have continued to occur
in the park in the face of deficient law enforcement [26,
Cervera et al. unpublished results]. Engaging local com-
munities in environmental policies is vital for the success
of conservation initiatives [27,28]. A good example of
consultation and involvement can be found in the rem-
nant dry forests around Zapotillo county (Loja Province)
in the south of Ecuador. In 2000, Nature and Culture
International (NCI) began working to create a network
of private ecological reserves in collaboration with local
communities. In this area, owing to the remoteness and
climate, the dry forests had not been cleared like in most
other areas in the country. With virtually no infrastruc-
ture present, and a climate hostile to agricultural use, the
area consisted of a few owners of vast haciendas, whose
principal activity of extensive goat and cow farming
depended on the dry forest ecosystem for stock feed and
shelter. Two co-managed reserves of 18 km
2
La Ceiba,
and Cazaderos, were established and now form part of
the BSBR. Importantly, local people contributed to the
establishment of protection policies and regulations for
forest use. Given that farmers make a living from goats
and the animals in turn forage in the forest, farmers
easily realized the forest needed to be protected to assure
their livelihood [Nature and Culture International,
https://natureandculture.org/]
The perceptions of people living nearby La Ceiba,
one of the co-managed reserves in Zapotillo, were
recently compared with those of people living near Are-
nillas Ecological Reserve [29]. Arenillas Ecological
Reserve (REA) was a military base and exclusion zone
since the 1970s due to its strategic location on the Peru
border. In 2001, responsibility for this area was trans-
ferred to the environmental ministry and the ecological
reserve was established. The perception of the protected
areas was usually positive in the case of La Ceiba (pro-
vision of ecosystem services, economic income by tour-
ism) and negative in the case of Arenillas Ecological
Reserve (restrictions of use, indifference) [29]. Like
Machalilla National Park, it seems that the people around
REA lack of sense of attachment and ownership of the
objectives of the protected area. Precisely these elements
seem critical in the achievement of conservation and sus-
tainable management goals. Given that dry forests are a
highly threatened ecosystem in the region, and are
under-represented in protected areas at the global scale,
additional forest reserves may be required to establish a
more robust conservation network, both from govern-
ment and local initiative, such as the examples of the
Zapotillo area and the Dry Forest Biosphere Reserve.
However, given the tight relationship between human
settlements, livelihoods and the dry forests, initiatives to
identify and declare new reserves should follow a gen-
uine process of consultation of local stakeholders, to
assure that the parks may contribute to effective and last-
ing conservation of the ecosystem [27,28].
Biodiversity patterns in the dry forests of the
Ecuadorian province: what do we know?
To review the existing studies about biodiversity in the
region, we performed a search in the Web of Science
portal, with the key words ‘tropical dry forest’AND
Ecuador* OR Peru*. The search (performed 18 April
2016) yielded 30 records, of which most were about
plants (60%), being almost 50% of those articles about
woody plants. The remaining articles were about birds
110 G. Escribano-Avila et al.

(17%), mammals (13%), insects (10%) and reptiles (3%).
According to this evidence, further research on the biodi-
versity patterns in the EP-TDF region is required for all
groups, but particularly for herpetofauna, fish, fungi and
invertebrates, which would be expected to be the most
species rich of all. Here, we provide some insights about
the current knowledge on species numbers, endemism
and conservation status for groups of woody plants,
birds, mammals, reptiles and amphibians.
Overall, EP-TDF is home of at least ~900 species of
trees, birds, mammals, amphibians and reptiles with an
average of 18% being endemic (range 25–6%) as shown
in Table 1. This is a high level of endemism similar to
that reported for the whole Tumbes-Chocó-Magdalena
region and other Neotropical biodiversity hotspots [11].
Around 30% of these endemic species are under some
threatened IUCN category (Table 1). Amongst tree spe-
cies, the richest taxonomic group of those well docu-
mented, 20% of the species are endemic to EP-TDF
[13,30]. There are 318 recorded tree species belonging to
180 genera and 54 families. Five families (Leguminosae,
Malvaceae, Boraginaceae, Cactaceae and Moraceae),
constitute around 40% of all recorded species; of those,
the Leguminosae alone accounts for 22% of species.
Most families, however, are represented by a few species
and 13 families by a single species. Woody species rich-
ness, considering trees and shrubs (DBH ≥5 cm), is
around 600 trees ha
−1
(538–625), while when including
individuals over 10 cm of DBH (thus probably excluding
shrubs) density values become lower and much variable
with a range of 22–524 trees ha
−1
(Table 2).
Birds are the second richest taxonomic group with an
estimated 250–300 species. Tropical dry forest of the
Ecuadorian Province (in the case of birds, better known
as Tumbesian region) sustains one of the highest
concentrations of species with restricted distribution in
South America [14] with 21% of species endemic to the
region, and 30% under some IUCN threatened category
[24,31–33], (Table 1). Although with much lower levels
of endemism, the mammal community is represented by
200 species, with 12 considered endemic [34,35]. Two
squirrel species deserve special mention in this regard,
the Guayaquil squirrel (Simosciurus stramineus), which
is endemic to the coast of Ecuador and distributed from
Esmeraldas to Guayas, and the white-napped squirrel
(Simosciurus nebouxii), which is found in the dry forests
of Arenillas, El Oro and north Piura, in Peru [36].
Amphibians and reptiles are also important compo-
nents of biodiversity in EP-TDF, contributing almost 100
species of which around 20% are endemic (see Table 1).
For reptiles, most species are snakes and lizards, one
species of blind snake, Amphisbaena occidentalis, and
one turtle (Rhinoclemmys annulata)[
37]. The conserva-
tion status of the herpetofauna, especially reptiles,
remains uncertain as the taxonomy is not well resolved.
For instance, the circumscription of several species of
snakes and lizards has recently been revised following
phylogenetic studies [38]. This is the case of the species
Lampropeltis micropholis,Erythrolamprus epinephelus,
and Alsophis elegans [39,40]. Taxonomic change is
rather common for tropical dry forest species, not just in
the case of the herpetofauna [41], but also for other
groups such as birds and mammals [42,43].
Aside from taxonomic revisions, the estimated ranges
of fauna from EP-TDF are also frequently modified as
field studies continue to produce new records. Some of
these recent examples are new records for the lizard
Macropholidus ruthveni [44] and the Tumbes tyrant
Tumbezia salvini [45] both recently confirmed in the
Zapotillo area, Province of Loja in southeastern Ecuador.
These examples highlight that more research is required
to understand patterns of biodiversity in these forests,
and to understand the effects of deforestation and anthro-
pogenic activities on the distribution and species conser-
vation status [46]. As more work is conducted, often
with improved techniques to study the distribution and
abundance of species (especially cryptic and elusive
ones), it is to be expected that changes in the conserva-
tion status will arise. A better understanding of both tax-
onomy and conservation status is required, considering
that Neotropical dry forests constitute a hotspot of defau-
nation. A global phenomenon that is especially worri-
some in the tropics [47].
Ecosystem function and risk in tropical dry forests of
the Ecuadorian province: a gap of knowledge
Given the immature state of knowledge of some individ-
ual taxa in EP-TDF, and the urgency of their conserva-
tion, a dual focus on improving species knowledge, and
ecosystem level function and risk, should be pursued.
Based on the policy success of the IUCN red list of spe-
cies, an international movement to develop criteria for
the recognition of globally threatened ecosystems was
initiated in the early 2000s to create the IUCN Red List
of Ecosystems [48]. Importantly, an ecosystem level
approach underlines the fundamental structural and engi-
neering role that common species play in the mainte-
nance of ecosystems and the functions that they generate
[49], as well as gathering essential information about the
distribution and status of rare and threatened species. In
recent years, the ecosystem risk assessment criteria and
method of application have been improved [50,51] and
could now be considered for application in EP-TDF.
These criteria include: rates of ecosystem loss and
Table 1. Number of endemic species and their percentages.
Taxa Nº species Endemic (%) IUCN threaten (%)
Trees 318 67 (21) 11
Birds 250–300 59 (21) 34
Mammals 200 12 (6) 33
Reptiles 64 12 (19) 17
Amphibians 32 8 (25) 38
Neotropical Biodiversity 111

decline at the distribution range level, restricted
distributions continuously declining or threatened, envi-
ronmental degradation, degradation of biotic processes
(e.g. mutualistic interactions) and a quantitative risk of
ecosystem collapse as integrative indicator of all the
above mentioned.
Recent work has established that from the processes
involved in forest regeneration, those more vulnerable to
human impact are pollination and seed dispersal medi-
ated by mutualistic interactions between plants and ani-
mals [52]. The disruption of mutualisms is considered as
a key indicator of the IUCN criteria ‘biotic processes
degradation’[50,51]. Accordingly, in this section we
highlight some insights on key ecological interactions,
such as endozoochorus seed dispersal and plant regenera-
tion dynamics, that may aid in the development of a risk
assessment approach for the ecosystem.
In spite of not being the most abundant dispersal
syndrome, zoochorous species account for around 50%
of woody plants in Neotropical dry forests [53,54], espe-
cially in well preserved patches [55]. This is also the
case of EP-TDF, where up to 54% of woody species pre-
sent a zoochorous dispersal syndrome [54]. Following
disturbance, zoochorous species tend to be the last ones
to recover [56], leading to impoverished plant communi-
ties and also reduced food resources for animals and less
nutrient supply to soils [57]. Despite this, relatively little
is currently known about seed dispersal performed by
animals in EP-TDF. A search of the subject performed in
the Web of Science portal (on 19 November 2015) with
the terms (‘frugivory’AND ‘tropical dry forest’)OR
(‘endozoochory’AND ‘tropical dry forest’)OR
(‘epizoochory’AND ‘tropical dry forest’) lead to 18
publications. Most were about primates, birds and bats,
with very few about reptiles or herbivorous mammals.
Surprisingly, there were no studies dealing with carnivo-
rous mammals as seed dispersers, despite the recognized
importance of this group as seed dispersal agents
(reviewed in [58]). An investigation of the importance of
the last herbivore-megafauna inhabiting EP-TDF, the
white tailed deer (Odocoileus virginianus peruvianus)
and also a mesocarnivore, the sechuran fox (Lycalopex
sechurae Thomas, 1900) is currently underway (Jara-
Guerrero et al., Escribano-Avila et al. unpublished data).
These two mammals, seem to be important dispersers as
they consume and deposit seeds of at least 15 woody
species, most of which have been shown to be viable
after passing through deer and fox gut. Birds, primates,
carnivores and bats are known as relevant dispersers in
mostly all kinds of ecosystems with fleshy fruited spe-
cies. However, recent findings on dispersal patterns in
other Neotropical dry forest areas highlight the relevance
of non-typical dispersers, such as iguanas [59,60] and
small terrestrial mammals [61,62]. Such work leads to
the expectation that these groups of animals may be also
relevant in the dispersal process of TDF-EC and thereby
warrant further research.
Once a seed is dispersed, many processes act to
influence germination, early recruitment and further
stages until recruits reach reproductive adulthood [63].
Plant-plant interactions may play a key role in determin-
ing the spatial structure and diversity of plant communi-
ties in the EP dry forests [11]. Various authors propose
that certain individuals or species may facilitate the
recruitment of other species by modifying the surround-
ing micro-environmental conditions (e.g. [64,65]). This
hypothesis was tested in an Ecuadorian dry forest by
means of evaluating the behavior of species in relation
to their ability to attract or repel diversity, considered as
a facilitation or competition effect respectively. At short
distances (≤10 m), about 30% of species behaved as
accumulators of diversity, or more still (over 50%), when
the relationship was assessed between juveniles [66].
Some ongoing work in dry scrublands of the Ecuadorian
Province show higher recruitment success under the
fringe of the canopy of the dominant shrub compared
with open areas. Furthermore, the relationship was modi-
fied by environmental stress; seedlings were more depen-
dent on facilitation in more stressful habitats (Quintana
et al. unpublished data). Although this demonstration
pertains to scrubland rather than forest, and should be
further developed to test generality, these findings
suggest that positive interactions between plants may be
relevant in the maintenance of biodiversity and regenera-
tion dynamics in EP-TDF. A greater understanding of
these dynamics and interactions in the dry forest ecosys-
tem should prove useful to guide management and strate-
gic documents, such as restoration plans.
Table 2. Diversity and density typical values of the dry forests of the Ecuadorian province. Note the minimum diameter threshold.
DBH
(cm)
Density trees
(Ha
−1
)
Richness Spp
(Ha
−1
)
Plot size
(Ha)
N
plots Country Locality Ref.
5 625 36 0,05 109 EC Zapotillo [69]
5 538 37 1 1 EC Machalilla NP [70]
5 588 4 9 1 EC Arenillas Ecol. Reserv. [73]
10 215 25 1 1 EC Machalilla NP [70]
10 22–524 6–25 1 6 PE Cerros de Amotape
NP
[71]
10 31–399 8–37 1 10 PE Cerros de Amotape
NP
[72]
112 G. Escribano-Avila et al.

Future challenges
Towards bi-national protection and management of the
tropical dry forest of the Ecuadorian province
Tropical dry forests of the Ecuadorian Province extend
over Ecuador and Peru. Whilst both countries have
established protected areas to preserve the forest, better
coordination could improve the connectivity of those
reserves, and consider the management of strategic areas
in the matrix between them. Both nations have declared
their intent to establish a Bi-National UNESCO reserve
that would protect 17000 km
2
including dry forests and
associated ecosystems (i.e. mangroves and wetlands).
This will allow the coordination of conservation aims
and management procedures. One of the proposed targets
of this bi-national reserve is to support the development
of a conservation culture, whereby local communities
may generate economic activities, such as ecotourism
(e.g. birdwatching, trekking or bicycle tours to enjoy the
Guayacan (Tabebuia spp) blooming). These options will
lead to widen the sources of economic income in the
local region and, at the same time, promote the conserva-
tion of dry forests. This initiative is already supported by
both countries and has been recently presented in the 4th
World Congress of Biosphere Reserves-UNESCO, held
in Lima, Peru on March 2016. We suggest that the work
being performed in this regard may be useful and inspir-
ing for both nations to collaborate towards an ecosystem
risk assessment process for EP-TDF. The process of doc-
umentation, and analysis of risks and opportunities for
the forests, should foster improved international coordi-
nation and collaboration in designing a sustainable future
for the region and its people.
Joint projects of research, innovation and management
may lead to achieve sustainable development in
equatorial pacific dry forests
Protected areas are a pivotal instrument toward the con-
servation of EP-TDF, however human use of these for-
ests, even in protected areas, is the rule rather than the
exception. Thus, it is necessary to seek compromises that
permit sustainable development of economic activities by
local communities alongside biodiversity conservation.
Research and innovation may be of great help in this
regard. A good example is the Palo Santo project (this is
the common name given in Ecuador to Bursera grave-
olens (Burseraceae)), which proposes to manage one of
the most widespread and dominant trees in EP-TDF. A
valuable essential oil is obtained from B. graveolens,
typically from the trunk, and thus the exploitation of this
economic resource is at the expense of forest conserva-
tion. The chemistry department of Universidad Técnica
Particular de Loja (UTPL) developed a methodology to
extract the essential oil from the fruits instead of the
trunk; this was the first step of the Palo Santo project
that brought together local communities, government
institutions and local NGOs, such as the aforementioned
NCI. The Palo Santo project resulted in the commercial-
ization of B. graveolens essential oil to the Brazilian
environmental enterprise Natura used in their natural
cosmetic products. Most project management is carried
out by the community association Bolívar Tello Cano.
This is probably the most remarkable example of how
the natural resources of dry forests may be used in a sus-
tainable manner, in addition to create social networking
and support local economies. Actually, in 2014 the
Bolívar Tello Cano community association was awarded
the United Nations Development Programme’s Equator
Prize, in recognition of the Palo Santo project’s
outstanding effectiveness in reducing poverty through
biodiversity conservation and sustainable business
practices [67].
Researchers could seek to play a similarly creative
and catalytic role in the development of sustainable
initiatives from the products and management of sting-
less native melaponid bees (Melipona spp). Ancestral
knowledge of the management of indigenous Melipona
bees has almost been lost due to habitat deterioration
and the introduction of the European bee (Apis
melifera). However, there are still some areas in which
meliponeculture still remains active, and these examples
may serve as a base to recover and expand this ances-
tral knowledge and the resources that Melipona bees
may provide. Researchers working together with local
people could assist in recovering and codifying ances-
tral knowledge for its dissemination to other interested
local communities, and at the same time increase scien-
tific information on the biology and conservation of
Melipona bees [68].
Concluding remarks
Tropical dry forests of the Ecuadorian Region are home
of at least 900 species of trees, birds, mammals, amphib-
ians and reptiles. Around one in five of these species are
endemic to the region, and many of them are threatened
with extinction. These numbers, already startling, are
likely to be conservative, as much remains to be learned
about several groups such as mammals, fish, fungi and
especially invertebrates, the most diverse living group in
the world. It is possible that many species may go
extinct before being discovered owing to the ongoing
deforestation and fragmentation condition of EP-TDF.
However, the growing number of protected areas with a
strong focus on co-management with local people
together with initiatives of sustainable development are
encouraging and signaling the way forward. The IUCN
process for the Red Listing of Ecosystems should serve
as inspiration and direction for targeted research in EP-
TDF. This research should address identified gaps in
knowledge required for conservation, but also contribute
to the development of sustainable options for local
communities that are required to facilitate the long term
conservation of EP-TDF.
Neotropical Biodiversity 113

Author contributions
Gema Escribano-Ávila designed, led the manuscript and
performed most of scientific literature review; David
Duncan provided guidance with the manuscript structure,
content section and English language; Laura García
Cervera contributed in art work. All authors actively
collaborated in the literature revision of their field of
expertise and manuscript writing (People-Forest interac-
tions: Joahana Briceoño, Bruno Paladines; Mammal
patterns: Laura García Cervera and Diego Lizcano; Bird
patterns: Leonardo Ordoñez; Herpetofauna patterns:
Luis Amador; Plant patterns and seed dispersal: Andrea
Jara-Guerrero, Carlos Iván Espinosa, Gema Escribano-
Ávila and Violeta Parés-Jimenez). All authors critically
reviewed the manuscript.
Associate Editor: Elisa Bonaccorso.
Disclosure Statement
No potential conflict of interest was reported by the
authors.
Funding
This work was supported by the Research Program of
Universidad Técnica Particular de Loja through the project
CCNN-1054. Gema Escribano-Ávila was supported by the
Prometeo Project of the Secretary for Higher Education,
Science, Technology and Innovation of Ecuador (SENESCYT).
ORCID
Gema Escribano-Avila http://orcid.org/0000-0003-1362-8924
Leonardo Ordóñez-Delgado http://orcid.org/0000-0002-
4593-1728
Andrea Jara-Guerrero http://orcid.org/0000-0001-9394-2790
Luis Amador http://orcid.org/0000-0003-2638-4068
Joahana Briceño http://orcid.org/0000-0002-3056-4734
Violeta Parés-Jiménez http://orcid.org/0000-0001-5346-6566
Diego J. Lizcano http://orcid.org/0000-0002-9648-0576
David H. Duncan http://orcid.org/0000-0003-4411-8214
Carlos Iván Espinosa http://orcid.org/0000-0002-5330-4505
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